Ligand-drug conjugates

Abstract

The present invention generally relates to ligand-drug conjugates of Formula I: or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof. The present invention further relates to the use of compounds of Formula I for the treatment of cancer. TIFF2026501817000420.tif44170

Description

[Technical Field]

[0001] The present invention relates generally to novel small molecule PSMA ligand-containing drug conjugates that selectively target PSMA-expressing tumor cells and cause their death through the release of a toxic drug payload. Furthermore, the present invention relates generally to the use of such drug conjugates for the treatment of cancer. [Background technology]

[0002] Prostate cancer is the most common cancer in men and is one of the leading causes of cancer deaths, despite recent advances in early diagnosis and treatment. Metastatic prostate cancer further reduces a patient's chances of survival. Androgen deprivation therapy has long been used to treat metastatic prostate cancer. Patients initially respond well to this treatment, but later progress from the castration-sensitive stage to the castration-resistant stage as their response to androgen deprivation therapy decreases. Several drugs are used in combination with androgen deprivation therapy to reduce or stop the progression to the castration-resistant stage. However, there are few effective treatments for advanced prostate cancer, including metastatic castration-resistant prostate cancer, androgen-independent prostate cancer, or recurrent prostate cancer.

[0003] Prostate-specific membrane antigen (PSMA), also known as N-acetyl-L-aspartyl-L-glutamate (NAAG) peptidase or glutamate carboxypeptidase II, is a zinc-containing metalloenzyme transmembrane glycoprotein normally expressed in healthy human tissue and normal prostate epithelium. It is overexpressed in prostate adenocarcinoma cells compared with benign prostate tissue. The degree of PSMA overexpression directly correlates with the stage and grade of tumor progression and malignancy in prostate cancer patients [see Silver, David A., et al., Wright Jr, George L., et al., Bostwick, David G., et al., and Mannweiler, Sebastian, et al.]. Increased PSMA expression is often observed to correlate with the development of advanced-stage cancers, such as metastatic or castration-resistant prostate cancer (CRPC), and has also been associated with a risk of recurrence after surgical intervention [see Wright Jr, George L., et al.; Ross, Jeffrey S., et al.; Mitsiades, Constantine S., et al.]. PSMA has a high propensity for internalization upon binding to antibodies or ligands. This aspect has been exploited in the development of radiopharmaceuticals and antibody drug conjugates (ADCs) for diagnostic and therapeutic purposes [see Liu, He, et al.].

[0004] Some of the reported PSMA-targeting ADCs are MLN2704 (PSMA-antibody MLN591-maytansine conjugate) [see Galsky, Matthew D., et al.], PSMA-ADC (PSMA-antibody-monomethyl auristatin E (MMAE)) conjugate [see Ma, Dangshe, et al.], and MEDI3726 (ADCT-401) [see Song Cho, et al.].

[0005] PSMA ligands conjugated with small molecules have emerged as PSMA-targeted imaging agents, therapeutics, and / or theranostic agents, offering unique advantages over ADCs due to their faster in vivo distribution, kinetics, more efficient penetration into solid tumors, and less adverse immunogenic responses. Furthermore, they are single synthetic entities with robust reproducibility and low manufacturing costs (see Xiankai Sun et al.). Some PSMA ligands conjugated with small molecules have been reported in U.S. Patent No. 6,479,470 (B1), Kozikowski et al., WO 2006093991 (A1), and U.S. Patent No. 6,528,499.

[0006] For diagnostic purposes, the ligands are radiolabeled and used as imaging agents to detect PSMA-expressing cancers. Such imaging agents are reported in U.S. Patent Nos. 7,408,079 (B2) and 8,487,129 (B2). Furthermore, there are several reports in which PSMA-binding ligands are conjugated to radiolabeled molecules via linkers. U.S. Patent No. 10,398,791 describes: 177Lu Vipivotide tetraxetan (PLUVICTO®), which was recently approved by the US Food and Drug Administration (FDA) for the treatment of adult patients with prostate-specific membrane antigen (PSMA)-positive metastatic castration-resistant prostate cancer (mCRPC) who have been treated with androgen receptor (AR) pathway inhibition and taxane-based chemotherapy. Gallium Ga-68 gozetotide (LOCAMETZ®) is disclosed in US Patent No. 11,369,590 (B2), and Sung-Hyun Moon et al. disclose another radiolabeled compound comprising a gallium radioisotope coordinated to a PSMA-binding ligand, a linker, and a chelating group. These gallium-based compounds are used as diagnostic agents for positron emission tomography (PET) imaging of PSMA-positive lesions in men with suspected metastatic or recurrent prostate cancer. Piflufolastat F-18 (PYLARIFY®), disclosed in U.S. Patent No. 8,487,129 (B2), is yet another radioactive diagnostic agent similar to LOCAMETZ®.

[0007] U.S. Patent No. 10,016,519 (B2), European Patent Application No. 2862857 (A1), U.S. Patent No. 9,056,841 (B2), WO 2020083853 (A1), and U.S. Patent No. 9,861,713 (B2) are some of the other patents / applications that disclose radioisotopes of metals coordinated to chelating groups linked to PSMA-binding ligands.

[0008] Although PSMA-targeted radiopharmaceuticals for diagnostic and therapeutic purposes currently aid in prostate cancer treatment regimens, they suffer from significant drawbacks, including manufacturing challenges, off-target toxicity, and the need for specialized settings or facilities for handling and administering radioactive materials.

[0009] WO 2022108992 discloses a non-radioactive compound comprising a PSMA-targeting ligand, a cleavable linker, and a cytotoxic chemotherapeutic agent, monomethyl auristatin E (MMAE). Such ligand-linker conjugates have also been reported in WO 2021101407 (A1), Russian Patent No. 2697519 (C1), U.S. Patent Application Nos. 11,202,836 (B2), and 9,193,763 (B2).

[0010] Thus, there remains a need to develop agents that are highly selective for cancer cells that express PSMA and that are therapeutically effective in treating such cancers. It is an object of the present invention to provide options for developing and meeting these needs. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] U.S. Patent No. 6,479,470 [Patent Document 2] International Publication No. 2006 / 093991 [Patent Document 3] U.S. Patent No. 6,528,499 [Patent Document 4] U.S. Patent No. 7,408,079 [Patent Document 5] U.S. Patent No. 8,487,129 [Patent Document 6] U.S. Patent No. 10,398,791 [Patent Document 7] U.S. Patent No. 11,369,590 [Patent Document 8] U.S. Patent No. 10,016,519 [Patent Document 9] European Patent Application Publication No. 2862857 [Patent Document 10] U.S. Patent No. 9,056,841 [Patent Document 11] International Publication No. 2020 / 083853 [Patent Document 12] U.S. Patent No. 9,861,713 [Patent Document 13] International Publication No. 2022 / 108992 [Patent Document 14] International Publication No. 2021 / 101407 [Patent Document 15] Russian Patent No. 2697519 [Patent Document 16] U.S. Patent No. 11,202,836 [Patent Document 17] U.S. Patent No. 9,193,763 Summary of the Invention

[0012] 2-(3-((S)-5-amino-1-carboxypentyl)ureido)pentanedioic acid, 2-[3-(1,3-dicarboxypropyl)ureido]pentanedioic acid, or 2-[3-(1-carboxy-2-mercapto-ethyl)ureido]pentanedioic acid are known as PSMA binding ligands.

[0013] The present invention relates generally to compounds comprising a PSMA-binding ligand conjugated to a cytotoxic or therapeutic agent via a linker.

[0014] In a first aspect of the present invention, a compound of formula I

[0015] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: n is 0, 1, 2, 3, or 4; L is a ligand; R1 is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, A binds to Q via its C-terminus, Q is a self-immolative group; Compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, are provided wherein D is a cytotoxic agent or a therapeutic agent.

[0016] In a second aspect of the present invention, a compound of formula II

[0017] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: n is 0, 1, 2, 3, or 4; L is a ligand; R1 is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; R4 is -C 1-10Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 But, H, -C 1-3 Alkyl or -C 1-3 Alkyl-OC 1-3 alkyl-OH; R 20 But H or -C 1-3 is alkyl, R 21 is H or -C1-C3 alkyl; Het2 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0018] [ka] is selected from R 15 is hydrogen or C 1-3 is alkyl, R 16 is hydrogen or C 1-3 alkyl, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 17 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 18 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5Alkynyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 or R 25 is hydrogen or C1-C3 alkyl, R 26 is hydrogen or C1-C3 alkyl, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; Compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, are provided wherein D is a cytotoxic agent or a therapeutic agent.

[0019] In a third aspect of the present invention, a compound of formula III

[0020] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, CH, or —C2H4—O—C2H4—OH; R 20 is CH3 and R 21 is CH3, Het2 is pyrrolidinyl, R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0021] [ka] is selected from R 15 is -CH3 or -C2H5, and R 16 is -CH3 or -C2H5, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 17 is -C(O)NHC2H4N(CH3)2, R 18 is -C(O)NHC2H4N(CH3)2 or or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )R 24 , or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 or

[0022] [ka] is selected from R 25 is -CH3 or -C2H5, R 26 is —CH3 or —C2H5, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 27 But -C(O)NH-C 2-5 alkyl-N(CH3)2, R 28 But -C(O)NH-C 2-5 alkyl-N(CH3)2 or or R 23 and R 24 together with the nitrogen to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3Provided are compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, wherein D is substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2, and D is a cytotoxic agent or therapeutic agent.

[0023] In a fourth aspect of the present invention, a compound of formula IV

[0024] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, —CH3, or —C2H4-O—C2H4-OH; R 20 is -CH3 and R 21 is -CH3, Het2 is pyrrolidinyl, R 14 -C1-C5 alkyl, -C1-C5 alkyl-N(R 15 )(R 16 ), -C1-C5 alkyl-OCH3, (-C2H4O) 1-10 CH2-CH3, or

[0025] [ka] is selected from R 15 But C 1-3 is alkyl, R 16 But C 1-3

[0023] Provided are compounds, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R is alkyl;

[0026] In a fifth embodiment, a compound of formula V

[0027] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, —CH3, or —C2H4-O—C2H4-OH; R 20 is -CH3 and R 21 is -CH3, Het2 is pyrrolidinyl, R 14 -C1-C5 alkyl, -C1-C5 alkyl-N(R 15 )(R 16 ), -C1-C5 alkyl-OCH3, (-C2H4O) 1-10 CH2-CH3, or

[0028] [ka] is selected from R 15 But C 1-3 is alkyl, R 16 But C 1-3 is alkyl, R 24 But -C 1-5 Alkyl, -C 1-5 Alkyl-N(R 25)(R 26 ), -C 1-5 Alkyl-OCH3, (-C2H4O) 1-10 CH2-CH3, or

[0029] [ka] is selected from R 25 is hydrogen or C 1-3 is alkyl, R 26 is hydrogen or C 1-3

[0023] Provided are compounds, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R is alkyl;

[0030] In a sixth embodiment, a compound of formula VI

[0031] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, CH, or —C2H4—O—C2H4—OH; R 20 is CH3 and R 21 is CH3, Het2 is pyrrolidinyl, R 12 is hydrogen, -C(O)N(R 13 )R 14 , or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -CH3,

[0032] [ka] -C 1-3 Alkyl-N(R 15 )(R 16 ), -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 17 , -CH2-triazole-(-C2H4O)4-C2H4-R 18 , or

[0033] [ka] and R 15 is -CH3 or -C2H5, R 16 is —CH3 or —C2H5, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 17 is -C(O)NHC2H4N(CH3)2, R 18 is -C(O)NHC2H4N(CH3)2 or or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -CH3,

[0034] [ka] -C 1-3 Alkyl-N(R 25 )(R 26 ), -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 27 , -CH2-triazole-(-C2H4O)4-C2H4-R 28 , or

[0035] [ka] and R 25 is -CH3 or -C2H5, R 26 is —CH3 or —C2H5, or R 25and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 27 is -C(O)NHC2H4N(CH3)2, R 28 is -C(O)NHC2H4N(CH3)2 or or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; Compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, are provided wherein D is a cytotoxic agent or a therapeutic agent.

[0036] In a seventh embodiment, a compound of formula VI

[0037] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, During the ceremony, L is a ligand and D is a cytotoxic or therapeutic agent; n is 0, 1, or 2; R1 is selected from the group consisting of phenyl, indolyl, thiophenyl, quinolinyl, and isoquinolinyl; R1 is unsubstituted or substituted with one or more R5; R5 is selected from halogen, —OH, or a 6- to 10-membered aryl ring; R2 is cyclohexyl or phenyl; A compound, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, is provided wherein A is the peptide val-cit.

[0038] In an eighth aspect, there is provided a method for treating a disease associated with PSMA-expressing cells, the method comprising administering a compound according to any one of the preceding aspects or a medicament comprising same.

[0039] In a ninth aspect, the present invention provides a method of treating cancer by administering a medicament comprising a compound selected from the group consisting of a compound of formula I, a compound of formula II, a compound of formula III, a compound of formula IV, a compound of formula V, a compound of formula VI, and a compound of formula VII, and a pharmaceutically acceptable excipient.

[0040] In a tenth aspect, the present invention provides a method of treating cancer comprising cells positive for expression of PSMA, the method comprising administering a compound, or a medicament comprising a compound, selected from the group consisting of a compound of formula I, a compound of formula II, a compound of formula III, a compound of formula IV, a compound of formula V, a compound of formula VI, and a compound of formula VII.

[0041] In an eleventh aspect, the present invention provides use of a compound selected from the group consisting of a compound of formula I, a compound of formula II, a compound of formula III, a compound of formula IV, a compound of formula V, a compound of formula VI, and a compound of formula VII for the preparation of a medicament for use in the treatment of a disease associated with PSMA-expressing cells.

[0042] In a twelfth aspect, the present invention provides a pharmaceutical composition comprising a compound selected from the group consisting of a compound of formula I, a compound of formula II, a compound of formula III, a compound of formula IV, a compound of formula V, a compound of formula VI, and a compound of formula VII, and a pharmaceutically acceptable carrier.

[0043] In a thirteenth aspect, the present invention provides a ligand-drug conjugate, wherein the ligand L and the drug D are represented by Formula VIII:

[0044] [ka] is conjugated via a linker of the formula: n is 0, 1, 2, 3, or 4; R1 is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, A binds to NH via its C-terminus, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from the group consisting of R 19 But hydrogen, -C 1-3 Alkyl or -C 1-3 Alkyl-OC 1-3 alkyl-OH; R 20 is hydrogen or -C 1-3 is alkyl, R 21 is hydrogen or -C1-3 alkyl, Het2 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R 12is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0045] [ka] is selected from R 15 is hydrogen or C1-C3 alkyl, R 16 is hydrogen or C1-C3 alkyl, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 17 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 18 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 or

[0046] [ka] is selected from R 25 is hydrogen or C1-C3 alkyl, R 26 is hydrogen or C1-C3 alkyl, or R 25 and R26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 Ligand-drug conjugates are provided that are substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2. DETAILED DESCRIPTION OF THE INVENTION

[0047] Definition: As used herein, "pharmaceutically acceptable salts" refers to derivatives of the disclosed compounds in which the parent compound is modified by making non-toxic acid or base salts thereof. Examples of pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of basic residues such as amines, alkali or organic salts of acidic residues such as carboxylic acids, etc. Pharmaceutically acceptable salts include, for example, the conventional non-toxic salts or quaternary ammonium salts of the parent compound formed from non-toxic inorganic or organic acids. For example, conventional non-toxic acid salts include those derived from hydrochloric acid, hydrobromic acid, sulfuric acid, sulfamic acid, phosphoric acid, nitric acid, etc., as well as salts prepared from organic acids such as acetic acid, propionic acid, glycolic acid, stearic acid, lactic acid, malic acid, tartaric acid, citric acid, ascorbic acid, pamoic acid, maleic acid, hydroxymaleic acid, phenylacetic acid, glutamic acid, aspartic acid, benzoic acid, salicylic acid, mesylic acid, sulfanilic acid, 2-acetoxybenzoic acid, fumaric acid, toluenesulfonic acid, methanesulfonic acid, ethanedisulfonic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, isethionic acid, etc. Pharmaceutically acceptable acid addition salts also include salts formed by the addition of one or more equivalents of acid, e.g., monohydrochlorides and dihydrochlorides.

[0048] The term "isotope" as used herein refers to an analog of a compound in which at least one atom in the compound is replaced with its isotope.For example, if at least one hydrogen atom is replaced with a deuterium atom, the resulting compound is called an isotope of the original compound.In particular, if a hydrogen atom in the original compound is replaced with a deuterium atom, the resulting compound is called a "deuterated analog".Isotopes can be fully or partially isotope-substituted derivatives.

[0049] As used herein, the term "stereoisomers" refers to compounds that have identical chemical constitution but differ with regard to the arrangement of their atoms or groups in space. The compounds of the present invention may contain asymmetric or chiral centers and, therefore, may exist in different stereoisomeric forms. Unless otherwise specified, all stereoisomeric forms of the compounds of Formulas I-VIII, and mixtures thereof, including racemic mixtures, are intended to form part of the present invention. In addition, all geometric and positional isomers (including E- and Z-forms), and mixtures thereof, are also encompassed within the scope of the present invention. In general, reference to a compound is intended to encompass that stereoisomer and mixtures of various stereoisomers.

[0050] The term "alkyl," as used herein, refers to a saturated hydrocarbon chain radical containing only carbon and hydrogen atoms in its backbone, either straight or branched, and having from 1 to 10 carbon atoms unless otherwise defined. Suitable non-limiting examples of alkyl groups include, for example, methyl, ethyl, n-propyl, 1-methylethyl (isopropyl), n-pentyl, and n-hexyl.

[0051] "C 1-4 " or "C1-C4" refers to the number of carbon atoms in the chain. 1-4 The term "alkyl" or "C1-C4 alkyl" refers to an alkyl chain having from 1 to 4 carbon atoms.

[0052] As used herein, the term "alkenyl" refers to a hydrocarbon chain containing at least one carbon-carbon double bond and may have an (E) or (Z) configuration. Alkenyl groups may contain 2 to 8 carbon atoms, unless otherwise specified. Unless otherwise stated or listed, all alkenyl groups described herein may form part of a straight or branched chain. Suitable, non-limiting examples of alkenyl groups include, for example, ethylene, 2-propenyl (allyl), 2-methyl-2-propenyl, and 2-butenyl. Unless otherwise stated or listed, all alkenyl groups described herein may be unsubstituted or substituted.

[0053] The term "alkynyl," as used herein, refers to a hydrocarbon chain containing at least one carbon-carbon triple bond. Such groups may contain 2 to 5 carbon atoms, unless otherwise specified. Unless otherwise stated or listed, all alkenyl groups described herein may form part of a straight or branched chain. Non-limiting examples of alkynyl groups are ethynyl, 2-propynyl, 1-propynyl, and 2-butynyl. The alkynyl groups of the present invention may be further substituted with alkenyl or alkyl groups as defined above.

[0054] The term "aryl" as used herein refers to an aromatic group having 6 to 14 carbon atoms and including monocyclic, bicyclic, or tricyclic aromatic systems. Bicyclic aryl groups include saturated, partially unsaturated rings, or aromatic rings fused to an aromatic ring. Bicyclic aryl groups can be attached to the rest of the molecule at any suitable position, including on the aromatic ring or the saturated or partially unsaturated ring. Typical aryl groups include, but are not limited to, phenyl, naphthyl, indanyl (e.g., 1-indanyl, 5-indanyl), indenyl, anthracenyl, and phenanthrenyl. Unless otherwise stated or listed, all aryl groups described herein can be unsubstituted or substituted. For example, aryl groups can be independently: C optionally substituted with one or more halogens (e.g., chloro, fluoro, iodo, or bromo). 1-4 alkyl (e.g., methyl, ethyl, propyl, and butyl); Phenyl;C 1-4 a 5- to 10-membered heteroaryl ring optionally substituted with one or more groups selected from alkyl; an amino group optionally further substituted with a substituted heteroaryl group; and COOH.

[0055] The term "heteroaryl ring" refers to a 5- to 14-membered aromatic heterocyclyl ring containing one or more (e.g., 1, 2, or 3) heteroatoms, each independently selected from nitrogen, oxygen, and sulfur. Heteroaryl rings can be monocyclic, bicyclic, or tricyclic ring systems, including fused ring systems (at least one of which is aromatic). The heteroaryl ring radical can be attached to the main structure at any heteroatom or carbon atom that results in the creation of a stable structure. Suitable examples of heteroaryl rings include, but are not limited to, oxazolyl, isoxazolyl, imidazolyl, furyl, indolyl, isoindolyl, pyrrolyl, triazolyl, triazinyl, tetrazolyl, thienyl, thiazolyl, isothiazolyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, benzofuranyl, benzothiazolyl, benzoxazolyl, benzimidazolyl, benzothienyl, benzopyranyl, carbazolyl, quinolinyl, isoquinolinyl, quinazolinyl, purinyl, quinoxalinyl, quinolinyl, isoquinolinyl, thiadiazolyl, indolizinyl, imidazo[1,2-a]pyridyl, and phthalazinyl. Unless otherwise stated or listed, all heteroaryl groups described or claimed herein can be unsubstituted or substituted.

[0056] The terms "heterocycloalkyl" or "heterocyclyl ring" are used interchangeably and refer to an aromatic or non-aromatic cyclic ring containing one, two, or three heteroatoms, each independently selected from nitrogen, sulfur, or oxygen. Suitable, non-limiting examples of heterocycloalkyl groups include those listed under "heteroaryl ring." Heterocycloalkyl groups can further include, but are not limited to, pyrrolidinyl, piperidine, piperazinyl, morpholinyl, thiomorpholine, and 1,3-oxazine. Unless otherwise stated or listed, heterocycloalkyl rings described herein can be unsubstituted or substituted.

[0057] As used herein, the term "self-immolative group" refers to a group that has a tendency to undergo a series of decomposition reactions, ultimately resulting in the release of an active molecule. Such a series of decomposition reactions is typically triggered by enzymatic activation of an amino acid or peptide (A) adjacent to the self-immolative group (Q). Enzymes such as cathepsin and plasmin are non-limiting examples of enzymes that trigger the self-immolative properties of the Q of the present invention.

[0058] The term "cytotoxic agent" as used herein refers to any agent that exerts a cytotoxic effect on cells upon contact. Such cytotoxic agents are well known to those skilled in the art. Examples of cytotoxic agents that can be used in the present invention include, but are not limited to, alkylating agents, anthracyclines, pyrimidine derivatives, vinca alkaloids, photodynamic agents, platinum-containing compounds, taxanes, topoisomerase inhibitors, ribosome-inactivating agents (e.g., gelonin), agents that induce DNA damage (e.g., calicheamicin), tubulin inhibitors (e.g., emtansine), antimitotic agents (e.g., monomethylauristatin), or bacterial toxins. The cytotoxic agent can also be a radioisotope or a cytotoxic antibody.

[0059] As used herein, the terms "therapeutic agent," "active ingredient," and "active agent" refer to an agent administered to treat a condition, disorder, or disease, or a symptom thereof. For purposes of this invention, a therapeutic agent is a known agent for the treatment of a disease or disorder involving cells that express PSMA.

[0060] The terms "subject" or "patient" are used interchangeably and refer to a subject that may benefit from the present invention, such as a mammal (e.g., a dog, cat, sheep, pig, horse, cow, or human). In a particular embodiment, the patient is a human. Diagnosis of a disease or disorder associated with expression of PSMA can be performed by a skilled physician by methods known in the art.

[0061] The term "subject in need thereof" in the context of the present invention refers inter alia to a mammalian, particularly a human, subject suffering from a disease or disorder associated with expression of PSMA.

[0062] The terms "disease" and "disorder" are used interchangeably.

[0063] As used herein, the term "cancer" refers to a disease caused by uncontrolled cell division and the ability of cells to metastasize, or establish new growths at additional sites. The terms "malignancy," "malignancy," "neoplasm," "tumor," "cancer," and variations thereof, refer to a cancerous cell or group of cancerous cells. For purposes of this invention, cancer is associated with expression of PSMA in cancerous cells, or cancer is associated with expression of PSMA in cells in the vicinity of the cancerous cells.

[0064] As used herein, the terms "treat," "treating," "treatment," or forms thereof, should be understood to mean reducing, preventing, curing, reversing, ameliorating, attenuating, mitigating, minimizing, suppressing, or arresting the deleterious effects of a disease or condition, or delaying the onset of one or more clinical symptoms of a disease or disorder.

[0065] A "therapeutically effective amount" of a compound is an amount sufficient to reduce or ameliorate the progression, severity, and / or duration of a disease or disorder, or ameliorate one or more symptoms of a disease or disorder, prevent the recurrence of a disease or disorder, or prevent the onset or development of a disease or disorder or one or more symptoms thereof. For purposes of this invention, a therapeutically effective amount is the amount of a compound of the invention administered to a subject to reduce or ameliorate the progression, severity, duration, or symptoms of a disease associated with expression of PSMA.

[0066] The terms "pharmaceutical composition," "medicament," and "dosage form" are used interchangeably and refer to a pharmaceutical preparation consisting of a drug substance(s) and / or excipient(s) to facilitate dosing or administration and delivery of the contents of the formulation to a subject. A drug substance is a compound that contains an active ingredient(s). For purposes of this invention, the compounds of Formulas I-VII are drug substances.

[0067] According to a first aspect of the present invention, a compound of formula I

[0068] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein n is 0, 1, 2, 3, or 4; L is a ligand; R1 is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; A is an amino acid or a peptide containing 2 to 5 amino acids, A binds to Q via its C-terminus, Q is a self-immolative group; Compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, are provided wherein D is a cytotoxic agent or a therapeutic agent.

[0069] According to one aspect of the present invention, a compound of formula I

[0070] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein n is 0, 1, 2, 3, or 4; L is a ligand; R1 is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, A binds to Q via its C-terminus, Q is a self-immolative group; Compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, are provided wherein D is a cytotoxic agent or a therapeutic agent.

[0071] The compounds of formula I can be described in one or more embodiments. It should be understood that the embodiments described herein are illustrative of the present invention and are not intended to be limiting. It should also be understood that the embodiments described herein can be used independently or in combination with any definition or any other embodiment defined herein. Thus, the present invention contemplates all possible combinations and permutations of the various embodiments described independently.

[0072] According to one embodiment, n is 0 and R1 is directly bonded to the carbon adjacent to -CO. According to another embodiment, n is 1, 2, 3, or 4 and R1 is bonded to the carbon adjacent to -CO via 1, 2, 3, or 4 methylene groups.

[0073] According to one embodiment, L is an antigen-binding ligand. According to a preferred embodiment, the ligand is a prostate-specific membrane antigen (PSMA)-binding ligand.

[0074] According to one embodiment, L is of formula L1:

[0075] [ka] is a ligand of the formula t1 is 0, 1, 2, 3, or 4; t2 is 1, 2, 3, or 4; Z is N(R9), Formula Z1, and Formula Z2:

[0076] [ka] wherein: t3 is selected from 1, 2, 3, 4, 5, or 6; t4 is selected from 1, 2, 3, 4, 5, or 6; Y is -CH2- or -NH-;

[0077] [ka] indicates the bond of formula L1 to the remainder of the compound of formula I, R9 is hydrogen, C 1-5 and R is selected from the group consisting of alkyl, 6- to 10-membered aryl, and 5- to 10-membered heterocyclyl ring, wherein the heterocyclyl ring contains 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and R is unsubstituted or substituted with halogen.

[0078] In one embodiment, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen.

[0079] In one embodiment, t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl.

[0080] In another embodiment, t1 is 3, t2 is 2, Z is N(R9), and the phenyl is substituted with Cl, Br, or I.

[0081] In one embodiment, t1 is 0, t2 is 2, Z is Z1, t3 is 1, 2, 3, 4, 5, or 6, and Y is -NH-.

[0082] In one embodiment, t1 is 1, t2 is 2, and Z is a compound of formula Z2.

[0083] In one embodiment, R1 is selected from phenyl, a fused bicyclic, or a fused tricyclic aromatic ring. In one embodiment, R1 is selected from a monocyclic or fused bicyclic heteroaromatic ring containing at least one heteroatom independently selected from nitrogen, oxygen, or sulfur.

[0084] In one embodiment, R1 is unsubstituted.

[0085] In one embodiment, R1 is substituted with Cl, Br, I, -OH, -C(O)NH2, -C(O)OH, -C(O)OCH3, -C(O)OC2H5, -CH3, -CH2CH3, -OCH3, -OCH2CH3, or phenyl.

[0086] In one embodiment, R2 is absent. In one embodiment, R2 is selected from a monocyclic or fused bicyclic aromatic or non-aromatic ring. In one embodiment, R2 is a monocyclic aromatic ring. In one embodiment, R2 is a monocyclic non-aromatic ring.

[0087] In one embodiment, when R2 is absent, R3 is H. In another embodiment, when R2 is absent, R3 is -C 1-5 Those skilled in the art will understand that when R2 is absent, the carbon atom containing R3 is directly bonded to -CO.

[0088] In one embodiment, R3 is H when R2 is selected from 6-10 membered cycloalkyl or 6-10 membered aryl.

[0089] According to one embodiment of the present invention, A is an amino acid or a peptide containing two or more of the same or different amino acids. The amino acid used in the present invention can be selected from natural or unnatural amino acids. It can be racemic or stereoisomers. In a specific embodiment, the amino acid used in the present invention is a stereoisomer. In another specific embodiment, the amino acid used in the present invention is dextrorotatory or levorotatory.

[0090] In one embodiment, the amino acid, at each occurrence, is independently alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a nucleotide sequence selected from the group consisting of Formula A1 and Formula A2.

[0091] [ka] and wherein the amino acid is selected from the group consisting of amino acids having the formula: m1 and m1' are 0, 1, 2, or 3; m2 and m2' are 0, 1, 2, 3, or 4; R 10 But (-C2H4O) 1-24 CH3, (-C2H4O) 1-24 C 1-2 Alkyl (N(R 10’ )(R 10’’ ))-, C 1-3 Alkyl-aryl, or -C 1-3Alkyl-Het1-(-C2H4O) 1-24 Het1 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and the aryl is selected from 6-14 membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R 10’ and R 10’’ are independently hydrogen, C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 Optionally substituted with alkyl.

[0092] In certain embodiments, the amino acids are independently selected from alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), citrulline (cit), homocitrulline (hct), homocysteine ​​(hcy), or an amino acid having formula A1 or formula A2, wherein: m1m1' is 0, 1, or 2, m2 is 2, m2' is 4, and R 10 But (-C2H4O) 6-8 and selected from CH3, (-C2H4O)3C2H4(NH(C(O)C3H6-aryl))-, C3H6-aryl, or -CH2-Het1-(-C2H4O)8CH3, where Het1 is triazolyl and aryl is 4-methylphenyl or 4-methoxyphenyl.

[0093] In one embodiment, in each occurrence, the peptide is independently selected from ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-gly-phe-gly, asp-cit, asp-val-cit, and asp-val, or the peptide has the following formula:

[0094] [ka]

[0095] [ka]

[0096] [ka] The compound is selected from the group of compounds having the formula:

[0097] According to one embodiment of the present invention, the self-immolative group Q has the formula Q1:

[0098] [ka] wherein: R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , and -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from the group consisting of R 19 But hydrogen, -C 1-3 Alkyl or -C 1-3 Alkyl-OC 1-3 alkyl-OH; R 20 is hydrogen or -C 1-3 is alkyl, R 21 is hydrogen or -C1-3 alkyl, Het2 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0099] [ka] is selected from R 15is hydrogen or C1-C3 alkyl, R 16 is hydrogen or C1-C3 alkyl, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 17 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 18 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25)(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 , or

[0100] [ka] is selected from R 25 is hydrogen or C1-C3 alkyl, R 26 is hydrogen or C1-C3 alkyl, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2;

[0101] [ka] indicates the attachment point of Q to the C-terminus of A, ** indicates the point of attachment of Q to D.

[0102] In one embodiment, in the compound of formula I, R 11 but, * -CH2OC(O)- ** ,

[0103] [ka] is selected from.

[0104] In one embodiment, in the compound of formula VIII, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0105] [ka] is selected from R 15 is selected from H, —CH3 or —C2H5; R 16 is selected from H, —CH3, or —C2H5; R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 17 is selected from hydrogen or —C(O)NH—C2H5—N(CH3)2, R 18 is selected from hydrogen or —C(O)NH—C2H5—N(CH3)2, Het3 is triazolyl.

[0106] In one embodiment, in the compound of formula VIII, R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 It is substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2.

[0107] In one embodiment, in the compound of formula VIII, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 , or

[0108] [ka] is selected from R 25 is selected from H, —CH3, or —C2H5; R 26 is selected from H, —CH3, or —C2H5; R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is selected from hydrogen or —C(O)NH—C2H5—N(CH3)2, R 28 is selected from hydrogen or —C(O)NH—C2H5—N(CH3)2, Het4 is triazolyl.

[0109] In one embodiment, in the compound of formula VIII, R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 It is substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2.

[0110] According to one embodiment of the present invention, D is an active ingredient having a cytotoxic or therapeutic effect.

[0111] One of the goals of the present invention is to provide an option for the selective treatment of diseases associated with PSMA-expressing cells or tissues. The compounds of the present invention are designed so that their selectivity is due to their ligand, and efficacy for treating the disease is achieved using drug D. Therefore, D for the present invention can be any active ingredient known or being investigated for the treatment of pathologies associated with PSMA hyperproliferation of cells. In addition to some prostate tissues, PSMA is expressed in various parts of the body, including, but not limited to, brain cells, kidney cells, bladder cells, colon cells, and breast cells. Diseases associated with these cells, particularly tumors or cancers, more specifically solid tumors, are targeted by the therapeutic agent (D) of the present invention.

[0112] In some embodiments, the therapeutic agent is a drug known for the treatment of cancer. In some other embodiments, the therapeutic agent is a drug known or being investigated for the treatment of a cancer associated with PSMA cell expression. In some other embodiments, the therapeutic agent is a drug known or being investigated in the treatment of prostate cancer, lung cancer, renal cell carcinoma, glioblastoma, pancreatic cancer, bladder cancer, breast cancer, colon cancer, esophageal cancer, gastric cancer, head cancer, neck cancer, head and neck cancer, colorectal cancer, leukemia / lymphoma, uterine cancer, skin cancer, endocrine cancer, urinary cancer, gastrointestinal cancer, ovarian cancer, or cervical cancer. Non-limiting examples of such therapeutic agents include olaparib, rucaparib, talazoparib, niraparib, veliparib; irinotecan, topotecan, exatecan, etoposide, teniposide, dabrafenib, entrectinib, larotrectinib, trametinib, selpercatinib, docetaxel, mobocertinib, infigratinib, tivozanib, tepotinib, pralsetinib, capmatinib, pemigatinib, tucatinib, neratinib, osimertinib, ceritinib, abemaciclib, rifapril ... These include bociclib, palbociclib, ripretinib, selumetinib, avapritinib, erdafitinib, lorlatinib, dacomitinib, encorafenib, brigatinib, alectinib, lenvatinib, cabozantinib, regorafenib, axitinib, alpelisib, tazemetostat, relugolix, darolutamide, apalutamide, sonidegib, enzalutamide, vismodegib, mitomycin, trabectedin, zildestrant, pemramettostat, and adavosertib.

[0113] In one embodiment, D is a cytotoxic agent as defined above. Some non-limiting examples of cytotoxic agents are microtubule disrupting agents, such as auristatins, e.g., monomethyl auristatin E (MMAE), monomethyl auristatin F (MMAF), and auristatin F (MMAF). F, AF); maytansinoids, such as DM1, DM3, and DM4; DNA damaging agents, such as calicheamicin, duocarmycin, SN-38, and pyrrolo[2,1-c][1,4]benzodiazepines (PBDs); amanitin, anthracyclines, baccatin, camptothecin, cemadotin, colchicine, colcimide, combretastatin, cryptophycin, discodermolide, doxorubicin, echinomycin, eleutherobin, epothilone, estramustine, lexitropsin, maytansine, methotrexate, netropsin, puromycin, rhizoxin, taxanes, tubulysin, or vinca alkaloids.

[0114] According to one embodiment, the present invention provides a compound of formula I, wherein: n is 0, 1, or 2; R1 is selected from a 6- to 10-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, at each occurrence, is independently selected from halogen, —OH, —OCH3, —OC2H5, or 6- to 10-membered aryl; R2 is selected from the group consisting of 5- to 6-membered cycloalkyl and 6- to 10-membered aryl; R3 is hydrogen; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is cit, ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-gly-phe-gly, formula P3, formula P5, formula P9, formula P 12 , formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of:

[0115] According to one embodiment, the present invention provides a compound of formula I, wherein: n is 1, R1 is naphthyl, R2 is cyclohexyl or phenyl; R3 is hydrogen; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is cit, ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-phe-gly, gly-gly-phe-gly, formula P3, formula P5, formula P9, formula P 12 , formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of Q is the formula Q1

[0116] [ka] wherein: ** indicates the point of attachment of Q to D, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from R 19 is selected from H, CH, or —C2H4—O—C2H4—OH; R 20 is CH3 and R 21 is CH3, Het2 is pyrrolidinyl, R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17, -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0117] [ka] is selected from R 15 is -CH3 or -C2H5, and R 16 is -CH3 or -C2H5, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 17 is -C(O)NHC2H4N(CH3)2, R 18 is -C(O)NHC2H4N(CH3)2, Het3 is triazolyl, or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 , or

[0118] [ka] is selected from R 25 is hydrogen or C1-C3 alkyl, R 26 is hydrogen or C1-C3 alkyl, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2;

[0119] [ka] indicates the attachment point of Q to the C-terminus of A, ** indicates the point of attachment of Q to D.

[0120] Those skilled in the art will understand that when R4 is a 3- to 6-membered cycloalkyl group, it may be bonded to adjacent groups on both sides through either the same or different carbons. For example, when R4 is a 5-membered cycloalkyl group, it may be bonded to adjacent groups as follows:

[0121] [ka]

[0122] According to some of the foregoing embodiments, the present invention provides compounds of Formula I, wherein R4 is -C 2-5 and A is selected from the group consisting of alkyl, -CH2=CH2-, -CH2-O-CH2-, -CH2(-OC2H4)2-OCH2-, and cyclobutyl; and A is selected from the group consisting of cit, val-ala, val-cit, gly-gly-phe-gly, or a group of formula P3, formula P5, formula P9, and formula P 12 In one embodiment, the present invention provides a compound of formula I, wherein R4 is -C 2-5 A is selected from the group consisting of cit, val-ala, val-cit, glu-val-cit, gly-gly-phe-gly.

[0123] According to one embodiment, the present invention provides a compound of formula I, wherein: n is 0, 1, or 2; R1 is selected from the group consisting of phenyl, indolyl, thiophenyl, quinolinyl, and isoquinolinyl; R1 is unsubstituted or substituted with one or more R5; R5 is selected from halogen, —OH, or a 6- to 10-membered aryl ring; R2 is cyclohexyl or phenyl; R3 is hydrogen; R4 is -C 1-10 is alkyl, A is val-cit, Q is the formula Q1

[0124] [ka] wherein: R 11 is -CH2OC(O)-, R 12 is hydrogen and R 22 is hydrogen.

[0125] According to one embodiment, the present invention provides a compound of formula I, wherein: n is 0, 1, or 2; R1 is selected from 6- to 10-membered aryl; R2 does not exist, R3 is -CH2COOH, -CH2CH2COOH, R4 is a 3- to 6-membered cycloalkyl; A is Cit, Q is the formula Q1

[0126] [ka] wherein: R 11 is -CH2-OC(O)-N(CH3)-C2H4-N(CH3)-C(O)-, R 12 is hydrogen and R 22 is hydrogen.

[0127] According to one embodiment, the present invention provides a compound of formula I, wherein: n is 0, 1, or 2; R1 is selected from 6- to 10-membered aryl; R2 is cyclohexyl or phenyl; R3 is hydrogen; R4 is -C 1-10 Alkyl- and -C 2-6 Alkyl(N(R8)(R 8’ ))-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is val-cit, gly-gly-phe-gly, formula P2, formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of Q is the formula Q1

[0128] [ka] wherein: R 11 is -CH2-OC(O)-, R 12 is hydrogen or -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen and R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) or

[0129] [ka] Selected from R 15 and R 16 are independently hydrogen and -C 1-5 alkyl, R 22 is hydrogen or -C(O)N(R 23 )(R 24 ) and R 23 is hydrogen and R 24 But -C 1-5 Alkyl-N(R 25 )(R 26 ), or

[0130] [ka] Selected from R 23 and R 24 are independently hydrogen and -C 1-5 alkyl, R 12 and R 22 At least one of is hydrogen.

[0131] In another aspect, the present disclosure provides a compound of formula I:

[0132] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand;

[0133] [ka] is selected from R1,

[0134] [ka] is selected from n is selected from 0, 1, and 2; R2 is not present, or

[0135] [ka] is selected from R3 is selected from hydrogen and —C2H4COOH; R4,

[0136] [ka] , -C 2-5 Alkyl, -CH=CH-, -CH2-O-CH2-, -CH2(-OC2H4) 2-8 -OCH2-,

[0137] [ka] is selected from A is selected from cit, val-cit, val-ala, gly-gly-phe-gly, glu-val-cit, gly-gly-phe, gly-phe-gly, Formula P1-ala, Formula P3, Formula P4-ala, Formula P5, Formula P9, Formula P12, Formula P13, and Formula P16; Q is,

[0138] [ka]

[0139] [ka] is selected from D is a cytotoxic or therapeutic agent selected from monomethyl auristatin E (MMAE), rucaparib, talazoparib, niraparib, SN-38, exatecan, belotecan, mitomycin C, and the like, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0140] In one embodiment, the present disclosure relates to a compound of Formula I, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a group of the formula:

[0141] [ka] is a ligand of R1,

[0142] [ka] and n is 1, R2,

[0143] [ka] and R3 is hydrogen; R4 is -C3H6-, A is val-cit, Q is,

[0144] [ka] and D is monomethyl auristatin E (MMAE).

[0145] In a second aspect of the present invention, a compound of formula II

[0146] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: n is 0, 1, 2, 3, or 4; L is a ligand; R1 is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 is hydrogen or C 1-6 is alkyl, A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)-** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 But, H, -C 1-3 Alkyl or -C 1-3 Alkyl-OC 1-3 alkyl-OH; R 20 But H or -C 1-3 is alkyl, R 21 is H or -C1-C3 alkyl; Het2 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R 12 is hydrogen, -C(O)N(R 13 )R 14 , or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )R 16 , -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , or -C 1-3 Alkyl-Het3-(-C2H4O)1-10 -C2H4-R 18 is selected from R 15 is hydrogen or C 1-3 is alkyl, R 16 is hydrogen or C 1-3 alkyl, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 17 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 18 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )R 24 , or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )R 26 , -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , or -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 is selected from R 25 is hydrogen or C1-C3 alkyl, R 26 is hydrogen or C1-C3 alkyl, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; Compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, are provided wherein D is a cytotoxic agent or a therapeutic agent.

[0147] In one embodiment of the present invention, a compound of formula II

[0148] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: n is 0, 1, 2, 3, or 4; L is a ligand; R1 is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 But, H, -C 1-3 Alkyl or -C1-3 Alkyl-OC 1-3 alkyl-OH; R 20 But H or -C 1-3 is alkyl, R 21 is H or -C1-C3 alkyl; Het2 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , or -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0149] [ka] is selected from R 15 is hydrogen or C 1-3 is alkyl, R 16 is hydrogen or C 1-3 alkyl, or R 15 and R 16together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 17 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 18 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R27 , or -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 , or

[0150] [ka] is selected from R 25 is hydrogen or C1-C3 alkyl, R 26 is hydrogen or C1-C3 alkyl, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; Provided are compounds, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein D is a cytotoxic or therapeutic agent as defined above.

[0151] According to one embodiment, the ligand in formula II is of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I.

[0152] In one embodiment, the ligand in formula II is of formula L1, where t1 is 0, t2 is 2, Z is Z1, t3 is 1, 2, 3, 4, 5, or 6, and Y is -NH-.

[0153] In one embodiment, the ligand in formula II is of formula L1, where t1 is 1, t2 is 2, and Z is a compound of formula Z2.

[0154] Furthermore, according to one embodiment, in formula II, A is alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group represented by formula A1 or formula A2.

[0155] [ka] and an amino acid selected from the group consisting of amino acids having the formula: m1 and m1' are 0, 1, 2, or 3; m2 and m2' are 0, 1, 2, 3, or 4; R 10 But (-C2H4O) 1-24 CH3, (-C2H4O) 1-24 C 1-2 Alkyl (N(R 10’ )(R 10’’ ))-, C 1-3 Alkyl-aryl, or -C 1-3 Alkyl-Het1-(-C2H4O) 1-24 Het1 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and the aryl is selected from 6-14 membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R 10’ and R 10’’ are independently hydrogen, C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 Optionally substituted with alkyl.

[0156] In another embodiment, in Formula II, A is a peptide selected from the group consisting of ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-phe-gly, gly-gly-phe-gly, asp-cit, asp-val-cit, and asp-val; or the peptide has the following formula:

[0157] [ka]

[0158] [ka]

[0159] [ka] The compound is selected from the group of compounds having the formula:

[0160] In one embodiment, the present invention provides a compound of formula II, wherein: L is of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I; R1 is naphthyl, R2 is a 6- to 10-membered cycloalkyl; R3 is hydrogen; R4 is -C 1-10 alkyl- or 3- to 6-membered cycloalkyl; A is an amino acid or peptide as mentioned in the previous embodiment; R 12 But -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) and R 15 is C1-C3 alkyl, R 16 is C1-C3 alkyl, R 22 is hydrogen.

[0161] In one embodiment, the present invention provides a compound of formula II, wherein: L is a ligand of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I; R1 is naphthyl, R2 is a 6- to 10-membered cycloalkyl; R3 is hydrogen; R4 is -C 1-10 alkyl- or 3- to 6-membered cycloalkyl; A is an amino acid or peptide as mentioned in the previous embodiment; R 12 But -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) and R 15 is C1-C3 alkyl, R 16 is C1-C3 alkyl, R 22 But -C(O)N(R 23 )(R 24 ) and R 23 is hydrogen, R 24 But -C 1-5 Alkyl-N(R 25 )(R 26 ) and R 25 But C 1-3 is alkyl, R 26 But C 1-3 It is alkyl.

[0162] In one embodiment, the present invention provides a compound of formula II, wherein: L is of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I; R1 is naphthyl, R2 is a 6- to 10-membered cycloalkyl; R3 is hydrogen; R4 is -C 1-10 Alkyl- or -C 2-6 Alkyl(N(R8)(R 8’ ))-selected from R8 and R 8’ are independently hydrogen, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl, and both R and R are not hydrogen; R and R' are independently hydrogen or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl, and both R and R' are not hydrogen; A is an amino acid or peptide as mentioned in the previous embodiment; R 11 But -C 1-3 Alkyl-OC(O)- ** is selected from ** indicates the point of attachment to D, R 12 But -C(O)N(R 13 )(R 14) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) and R 15 is C1-C3 alkyl, R 16 is C1-C3 alkyl, R 22 is hydrogen.

[0163] In another aspect, the present disclosure provides a compound of formula II:

[0164] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand;

[0165] [ka] is selected from R1,

[0166] [ka] is selected from n is selected from 0, 1, and 2; R2 is not present, or

[0167] [ka] is selected from R3 is selected from hydrogen and —C2H4COOH; R4,

[0168] [ka] , -C 2-5Alkyl, -CH=CH-, -CH2-O-CH2-, -CH2(-OC2H4) 2-8 -OCH2-,

[0169] [ka] is selected from A is selected from cit, val-cit, val-ala, gly-gly-phe-gly, glu-val-cit, gly-gly-phe, gly-phe-gly, Formula P1-ala, Formula P3, Formula P4-ala, Formula P5, Formula P9, Formula P12, Formula P13, and Formula P16;

[0170] [ka] but,

[0171] [ka]

[0172] [ka] is selected from D is a cytotoxic or therapeutic agent selected from monomethyl auristatin E (MMAE), rucaparib, talazoparib, niraparib, SN-38, exatecan, belotecan, and mitomycin C, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0173] In one embodiment, the present disclosure relates to a compound of formula II, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a group of the formula:

[0174] [ka] is a ligand of R1,

[0175] [ka] and n is 1, R2,

[0176] [ka] and R3 is hydrogen; R4 is -C3H6-, A is val-cit,

[0177] [ka] but,

[0178] [ka] and D is monomethyl auristatin E (MMAE).

[0179] In a third aspect of the present invention, a compound of formula III

[0180] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 is hydrogen or C 1-6 is alkyl, A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, CH, or —C2H4—O—C2H4—OH; R 20 is CH3 and R 21 is CH3, Het2 is pyrrolidinyl, R 12 is hydrogen, -C(O)N(R 13 )R 14 , or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -CH3,

[0181] [ka] -C 1-3 Alkyl-N(R 15 )R 16 , -C2H4OCH3, -(-C2H4O) 3-8-C2H5, -(-C2H4O) 5-10 -C2H4-R 17 , -CH2-triazole-(-C2H4O)4-C2H4-R 18 and R 15 is -CH3 or -C2H5, and R 16 is -CH3 or -C2H5, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 17 is -C(O)NHC2H4N(CH3)2, R 18 is -C(O)NHC2H4N(CH3)2 or or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )R 24 , or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -CH3,

[0182] [ka] -C 1-3 Alkyl-N(R 25 )R26 , -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 27 , -CH2-triazole-(-C2H4O)4-C2H4-R 28 is selected from R 25 is -CH3 or -C2H5, R 26 is —CH3 or —C2H5, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 27 But -C(O)NH-C 2-5 alkyl-N(CH3)2, R 28 But -C(O)NH-C 2-5 alkyl-N(CH3)2 or or R 23 and R 24 together with the nitrogen to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 Provided are compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, wherein D is substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2, and D is a cytotoxic agent or therapeutic agent.

[0183] In one embodiment of the present invention, a compound of formula III

[0184] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, CH, or —C2H4—O—C2H4—OH; R 20 is CH3 and R 21 is CH3, Het2 is pyrrolidinyl, R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -CH3,

[0185] [ka] -C 1-3 Alkyl-N(R 15 )(R 16 ), -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 17 , -CH2-triazole-(-C2H4O)4-C2H4-R 18 , or

[0186] [ka] and R 15 is -CH3 or -C2H5, and R 16is -CH3 or -C2H5, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 17 is -C(O)NHC2H4N(CH3)2, R 18 is -C(O)NHC2H4N(CH3)2 or or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -CH3,

[0187] [ka] -C 1-3 Alkyl-N(R 25 )(R 26 ), -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 27 , -CH2-triazole-(-C2H4O)4-C2H4-R 28 , or

[0188] [ka] is selected from R 25 is -CH3 or -C2H5, R 26 is —CH3 or —C2H5, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 27 But -C(O)NH-C 2-5 alkyl-N(CH3)2, R 28 But -C(O)NH-C 2-5 alkyl-N(CH3)2 or or R 23 and R 24 together with the nitrogen to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 Provided are compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, wherein D is substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2, and D is a cytotoxic or therapeutic agent as defined above.

[0189] According to one embodiment, the ligand in formula III is of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I.

[0190] In one embodiment, the ligand in formula III is a ligand of formula L1, where t1 is 0, t2 is 2, Z is Z1, t3 is 1, 2, 3, 4, 5, or 6, and Y is -NH-.

[0191] In one embodiment, the ligand in formula III is a ligand of formula L1, where t1 is 1, t2 is 2, and Z is a compound of formula Z2.

[0192] Furthermore, according to one embodiment, in formula III, A is alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group represented by formula A1 or formula A2.

[0193] [ka] and an amino acid selected from the group consisting of amino acids having the formula: m1 and m1' are 0, 1, 2, or 3; m2 and m2' are 0, 1, 2, 3, or 4; R 10 But (-C2H4O) 1-24 CH3, (-C2H4O)1-24 C 1-2 Alkyl (N(R 10’ )(R 10’’ ))-, C 1-3 Alkyl-aryl, or -C 1-3 Alkyl-Het1-(-C2H4O) 1-24 Het1 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and the aryl is selected from 6-14 membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R 10’ and R 10’’ are independently hydrogen, C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 Optionally substituted with alkyl.

[0194] In another embodiment, in Formula III, A is a peptide selected from the group consisting of ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-phe-gly, gly-gly-phe-gly, asp-cit, asp-val-cit, and asp-val; or the peptide has the following formula:

[0195] [ka]

[0196] [ka]

[0197] [ka] The compound is selected from the group of compounds having the formula:

[0198] In one embodiment, the present invention provides a compound of formula III, wherein: L is of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I; R4 is -C 1-10 alkyl- and 3- to 6-membered cycloalkyl; A is cit, val-ala, val-cit, gly-gly-phe-gly, formula P3, formula P5, formula P9, formula P 12 , formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of R 11 But -C 1-3 Alkyl-OC(O)- ** and ** indicates the point of attachment to D, R 12 But -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) and R 15 But C 1-3 is alkyl, R 16 But C 1-3 is alkyl, R 22 is hydrogen.

[0199] In one embodiment, the present invention provides a compound of formula III, wherein: L is of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I; R4 is -C 1-10 alkyl- and 3- to 6-membered cycloalkyl; A is cit, val-ala, val-cit, gly-gly-phe-gly, formula P3, formula P5, formula P9, formula P 12 , formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of R 11 But -C 1-3 Alkyl-OC(O)- ** and ** indicates the point of attachment to D, R 12 But -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) and R 15 But C 1-3 is alkyl, R 16 But C 1-3 is alkyl, R 22 But -C(O)N(R 23 )(R 24 ) and R 23 is hydrogen, R 24But -C 1-5 Alkyl-N(R 25 )(R 26 ) and R 25 But C 1-3 is alkyl, R 26 But C 1-3 It is alkyl.

[0200] In another aspect, the present disclosure provides a compound of formula III:

[0201] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand;

[0202] [ka] is selected from R4,

[0203] [ka] , -C 2-5 Alkyl, -CH=CH-, -CH2-O-CH2-, -CH2(-OC2H4) 2-8 -OCH2-,

[0204] [ka] is selected from A is selected from cit, val-cit, val-ala, gly-gly-phe-gly, glu-val-cit, gly-gly-phe, gly-phe-gly, Formula P1-ala, Formula P3, Formula P4-ala, Formula P5, Formula P9, Formula P12, Formula P13, and Formula P16;

[0205] [ka] but,

[0206] [ka]

[0207] [ka] is selected from D is a cytotoxic or therapeutic agent selected from monomethyl auristatin E (MMAE), rucaparib, talazoparib, niraparib, SN-38, exatecan, belotecan, and mitomycin C, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0208] In one embodiment, the present disclosure relates to a compound of formula III, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R4 is -C3H6-, A is val-cit,

[0209] [ka] but,

[0210] [ka] and D is monomethyl auristatin E (MMAE).

[0211] In a fourth aspect of the present invention, a compound of formula IV

[0212] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 is hydrogen or C 1-6 is alkyl, A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, —CH3, or —C2H4-O—C2H4-OH; R 20 is -CH3 and R 21 is -CH3, Het2 is pyrrolidinyl, R 14 -C1-C5 alkyl, -C1-C5 alkyl-N(R 15 )R 16 , -C1-C5 alkyl-OCH3, (-C2H4O) 1-10 selected from CH2-CH3, R 15 But C 1-3 is alkyl, R 16 But C 1-3

[0023] Provided are compounds, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R is alkyl;

[0213] In one embodiment of the present invention, a compound of formula IV

[0214] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand and D is a cytotoxic or therapeutic agent as defined above; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, —CH3, or —C2H4-O—C2H4-OH; R 20 is -CH3 and R 21 is -CH3, Het2 is pyrrolidine, R 14 -C1-C5 alkyl, -C1-C5 alkyl-N(R 15 )(R 16 ), -C1-C5 alkyl-OCH3, (-C2H4O) 1-10 CH2-CH3, or

[0215] [ka] is selected from R 15 But C1-3 is alkyl, R 16 But C 1-3

[0023] Provided are compounds, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R is alkyl;

[0216] According to one embodiment, the ligand in formula IV is of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I.

[0217] In one embodiment, the ligand in formula IV is of formula L1, wherein t1 is 0, t2 is 2, Z is Z1, t3 is 1, 2, 3, 4, 5, or 6, and Y is -NH-.

[0218] In one embodiment, the ligand in formula IV is of formula L1, where t1 is 1, t2 is 2, and Z is a compound of formula Z2.

[0219] Furthermore, according to one embodiment, in formula IV, A is alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group represented by formula A1 or formula A2.

[0220] [ka] an amino acid from the group consisting of amino acids having the formula m1 and m1' are 0, 1, 2, or 3; m2 and m2' are 0, 1, 2, 3, or 4; R 10 But (-C2H4O) 1-24 CH3, (-C2H4O) 1-24 C 1-2 Alkyl (N(R 10’ )(R 10’’ ))-, C 1-3 Alkyl-aryl, or -C 1-3 Alkyl-Het1-(-C2H4O) 1-24 Selected from CH3, Het1 is a 5- to 10-membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R 10’ and R 10’’ are independently hydrogen, C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 Optionally substituted with alkyl.

[0221] In another embodiment, in formula IV, A is a peptide selected from the group consisting of ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-phe-gly, gly-gly-phe-gly, asp-cit, asp-val-cit, and asp-val; or the peptide has the following formula:

[0222] [ka]

[0223] [ka]

[0224] [ka] The compound is selected from the group of compounds having the formula:

[0225] In one embodiment, the present invention provides a compound of formula IV, wherein: L is a ligand of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and phenyl is substituted with Cl, Br, or I; R4 is -C 2-5 Alkyl, -C 2-5 Alkyl(N(R8)(R 8’ ))-, and 3- to 6-membered cycloalkyl; R8 and R 8’ are independently hydrogen, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 2-6 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is cit, val-ala, val-cit, glu-val-cit, gly-gly-phe-gly, formula P3, formula P5, formula P9, formula P12 , formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of R 11 But -C 1-3 Alkyl-OC(O)- ** and ** indicates the point of attachment to D, R 12 But -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ), and

[0226] [ka] is selected from R 15 But C 1-3 is alkyl, R 16 But C 1-3 It is alkyl.

[0227] In another aspect, the present disclosure provides a compound of formula IV:

[0228] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand;

[0229] [ka] is selected from R4,

[0230] [ka] , -C 2-5 Alkyl, -CH2=CH2-, -CH2-O-CH2-, -CH2(-OC2H4) 2-8 -OCH2-,

[0231] [ka] is selected from A is selected from cit, val-cit, val-ala, gly-gly-phe-gly, glu-val-cit, gly-gly-phe, gly-phe-gly, Formula P1-ala, Formula P3, Formula P4-ala, Formula P5, Formula P9, Formula P12, Formula P13, and Formula P16; R 11 is selected from -CH2-OC(O)-,

[0232] [ka] but,

[0233] [ka]

[0234] [ka] is selected from D is a cytotoxic or therapeutic agent selected from monomethyl auristatin E (MMAE), rucaparib, talazoparib, niraparib, SN-38, exatecan, belotecan, mitomycin C, and the like, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0235] In one embodiment, the present disclosure relates to a compound of formula IV, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R4 is -C3H6-, A is val-cit,

[0236] [ka] but,

[0237] [ka] and D is monomethyl auristatin E (MMAE).

[0238] In a fifth embodiment, a compound of formula V

[0239] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 is hydrogen or C 1-6 is alkyl, A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R21 )]-C 1-3 Alkyl- ** , -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** , or -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, —CH3, or —C2H4-O—C2H4-OH; R 20 is -CH3 and R 21 is -CH3, Het2 is pyrrolidinyl, R 14 -C1-C5 alkyl, -C1-C5 alkyl-N(R 15 )R 16 , -C1-C5 alkyl-OCH3, (-C2H4O) 1-10 selected from CH2-CH3, R 15 But C 1-3 is alkyl, R 16 But C 1-3 is alkyl, R 24 But -C 1-5 Alkyl, -C 1-5 Alkyl-N(R 25 )R 26 , -C 1-5 Alkyl-OCH3, (-C2H4O) 1-10 selected from CH2-CH3, R 25 is hydrogen or C 1-3 is alkyl, R 26 is hydrogen or C 1-3

[0023] Provided are compounds, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R is alkyl;

[0240] In one embodiment, formula V

[0241] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L and A are as defined in the previous embodiment; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 is hydrogen or C 1-6 is alkyl, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from **indicates the point of attachment to D, R 19 is selected from H, —CH3, or —C2H4-O—C2H4-OH; R 20 is -CH3 and R 21 is -CH3, Het2 is pyrrolidinyl, R 14 -C1-C5 alkyl, -C1-C5 alkyl-N(R 15 )(R 16 ), -C1-C5 alkyl-OCH3, (-C2H4O) 1-10 selected from CH2-CH3, R 15 But C 1-3 is alkyl, R 16 But C 1-3 is alkyl, R 24 But -C 1-5 Alkyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5 Alkyl-OCH3, (-C2H4O) 1-10 selected from CH2-CH3, R 25 is hydrogen or C 1-3 is alkyl, R 26 is hydrogen or C 1-3

[0023] Provided are compounds, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R is alkyl;

[0242] In one embodiment, the present invention provides a compound of formula V, wherein: L is a ligand of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl substituted with Cl, Br, or I; R4 is -C 2-5 selected from alkyl and 3- to 6-membered cycloalkyl; A is selected from the group consisting of cit, val-ala, val-cit, glu-val-cit, gly-gly-phe-gly; R 11 But -C 1-3 Alkyl-OC(O)- ** and ** indicates the point of attachment to D, R 12 But -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) and R 15 But C 1-3 is alkyl, R 16 But C 1-3 is alkyl, R 22 But -C(O)N(R 23 )R 24 and R 23 is hydrogen, R 24 But -C 1-5 Alkyl-N(R 25 )(R 26 ) and R 25 But C 1-3 is alkyl, R 26 But C 1-3 It is alkyl.

[0243] In a sixth embodiment, a compound of formula VI

[0244] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; A is an amino acid or a peptide containing 2 to 5 amino acids, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** , or -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, CH, or —C2H4—O—C2H4—OH; R 20 is CH3 and R 21 is CH3, Het2 is pyrrolidinyl, R 12 is hydrogen, -C(O)N(R 13 )R 14 , or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -CH3,

[0245] [ka] -C 1-3 Alkyl-N(R 15 )R 16 , -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 17 , -CH2-triazole-(-C2H4O)4-C2H4-R 18 and R 15 is -CH3 or -C2H5, R 16 is —CH3 or —C2H5, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 17 is -C(O)NHC2H4N(CH3)2, R 18 is -C(O)NHC2H4N(CH3)2 or or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )R 24 , or -(-OC2H4) 1-10 -CH3, R23 is hydrogen, R 24 But -CH3,

[0246] [ka] -C 1-3 Alkyl-N(R 25 )R 26 , -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 27 , -CH2-triazole-(-C2H4O)4-C2H4-R 28 and R 25 is -CH3 or -C2H5, R 26 is —CH3 or —C2H5, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 27 is -C(O)NHC2H4N(CH3)2, R 28 is -C(O)NHC2H4N(CH3)2 or or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; Compounds, or pharmaceutically acceptable salts, stereoisomers, or isotopes thereof, are provided wherein D is a cytotoxic agent or a therapeutic agent.

[0247] In one embodiment, Formula VI

[0248] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L and A are as defined in the previous embodiment; R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from ** indicates the point of attachment to D, R 19 is selected from H, CH, or —C2H4—O—C2H4—OH; R 20 is CH3 and R 21 is CH3, Het2 is pyrrolidinyl, R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -CH3,

[0249] [ka] -C 1-3 Alkyl-N(R 15 )(R 16 ), -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 17 , -CH2-triazole-(-C2H4O)4-C2H4-R 18 , or

[0250] [ka] and R 15 is -CH3 or -C2H5, R 16 is —CH3 or —C2H5, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 17 is -C(O)NHC2H4N(CH3)2, R 18 is -C(O)NHC2H4N(CH3)2 or or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -CH3,

[0251] [ka] -C 1-3 Alkyl-N(R 25 )(R 26 ), -C2H4OCH3, -(-C2H4O) 3-8 -C2H5, -(-C2H4O) 5-10 -C2H4-R 27 , -CH2-triazolyl-(-C2H4O)4-C2H4-R 28 , or

[0252] [ka] and R 25 is -CH3 or -C2H5, R 26 is —CH3 or —C2H5, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 27 is -C(O)NHC2H4N(CH3)2, R 28 is -C(O)NHC2H4N(CH3)2 or or R 23 and R 24together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; Provided are compounds, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein D is a cytotoxic or therapeutic agent as defined above.

[0253] In one embodiment, the present invention provides a compound of formula VI, wherein: L is a ligand of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl substituted with Cl, Br, or I; A is cit, val-ala, val-cit, gly-gly-phe-gly, formula P3, formula P5, formula P9, and formula P 12 is selected from the group consisting of R 11 But -C 1-3 Alkyl-OC(O)- ** and ** indicates the point of attachment to D, R 12 But -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) and R 15 But C 1-3 is alkyl, R16 But C 1-3 is alkyl, R 22 is hydrogen.

[0254] In one embodiment, the present invention provides a compound of formula VI, wherein: L is a ligand of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl substituted with Cl, Br, or I; A is cit, val-ala, val-cit, gly-gly-phe-gly, formula P3, formula P5, formula P9, and formula P 12 is selected from the group consisting of R 11 But -C 1-3 Alkyl-OC(O)- ** and ** indicates the point of attachment to D, R 12 But -C(O)N(R 13 )(R 14 ) and R 13 is hydrogen, R 14 But -C 1-5 Alkyl-N(R 15 )(R 16 ) and R 15 But C 1-3 is alkyl, R 16 But C 1-3 is alkyl, R 22 But -C(O)N(R 23 )(R 24 ) and R 23 is hydrogen, R 24 But -C1-5 Alkyl-N(R 25 )(R 26 ) and R 25 But C 1-3 is alkyl, R 26 But C 1-3 It is alkyl.

[0255] In another aspect, the present disclosure provides a compound of formula VI:

[0256] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand;

[0257] [ka] is selected from A is selected from cit, val-cit, val-ala, gly-gly-phe-gly, glu-val-cit, gly-gly-phe, gly-phe-gly, Formula P1-ala, Formula P3, Formula P4-ala, Formula P5, Formula P9, Formula P12, Formula P13, and Formula P16;

[0258] [ka] but,

[0259] [ka]

[0260] [ka] is selected from D is a cytotoxic or therapeutic agent selected from monomethyl auristatin E (MMAE), rucaparib, talazoparib, niraparib, SN-38, exatecan, belotecan, mitomycin C, and the like, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0261] In one embodiment, the present disclosure relates to a compound of formula VI, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: A is val-cit,

[0262] [ka] but,

[0263] [ka] and D is monomethyl auristatin E (MMAE).

[0264] In a seventh embodiment, a compound of formula VII

[0265] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, During the ceremony, L is a ligand and D is a cytotoxic or therapeutic agent; n is 0, 1, or 2; R1 is selected from the group consisting of phenyl, indolyl, thiophenyl, quinolinyl, and isoquinolinyl; R1 is unsubstituted or substituted with one or more R5; R5 is selected from halogen, —OH, or a 6- to 10-membered aryl ring; R2 is cyclohexyl or phenyl; A compound, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, is provided wherein A is the peptide val-cit.

[0266] In another embodiment, Formula VII

[0267] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, During the ceremony, L and D are as defined above, n is 0, 1, or 2; R1 is selected from the group consisting of phenyl, indolyl, thiophenyl, quinolinyl, and isoquinolinyl; R1 is unsubstituted or substituted with one or more R5; R5 is selected from halogen, —OH, or a 6- to 10-membered aryl ring; R2 is cyclohexyl or phenyl; A compound, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, is provided wherein A is the peptide val-cit.

[0268] In one embodiment, the compound is a compound of formula VII, wherein: L is a ligand of formula L1, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, L is a ligand of formula L1, where t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl substituted with Cl, Br, or I; R2 is a 6- to 10-membered cycloalkyl.

[0269] In another aspect, the present disclosure provides a compound of formula VII:

[0270] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand;

[0271] [ka] is selected from R1,

[0272] [ka] is selected from n is selected from 0, 1, and 2; R2 is not present, or

[0273] [ka] is selected from A is selected from val-cit, val-ala, gly-gly-phe-gly, glu-val-cit, and formula P3; D is a cytotoxic or therapeutic agent selected from monomethyl auristatin E (MMAE), rucaparib, talazoparib, niraparib, SN-38, exatecan, belotecan, mitomycin C, and the like, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0274] In one aspect, the present invention provides a ligand-drug conjugate, wherein the ligand L and the drug D are represented by Formula VIII:

[0275] [ka] is conjugated via a linker of the formula: n is 0, 1, 2, 3, or 4; R1 is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 is hydrogen or C 1-6 is alkyl, A is an amino acid or a peptide containing 2 to 5 amino acids, A binds to NH via its C-terminus, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R20 R 21 )]-C 1-3 Alkyl- ** , -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** , and -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** is selected from R 19 But hydrogen, -C 1-3 Alkyl or -C 1-3 Alkyl-OC 1-3 alkyl-OH; R 20 is hydrogen or -C 1-3 is alkyl, R 21 is hydrogen or -C1-3 alkyl, Het2 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R 12 is hydrogen, -C(O)N(R 13 )R 14 , or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )R 16 , -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , or -C 1-3 Alkyl-Het3-(-C2H4O)1-10 -C2H4-R 18 is selected from R 15 is hydrogen or C1-C3 alkyl, R 16 is hydrogen or C1-C3 alkyl, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 17 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 18 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )R 24 , or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C 2-5Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )R 26 , -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , or -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 is selected from R 25 is hydrogen or C1-C3 alkyl, R 26 is hydrogen or C1-C3 alkyl, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3Ligand-drug conjugates are provided that are substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2.

[0276] In yet another aspect, the present invention provides a ligand-drug conjugate, wherein the ligand L and the drug D are represented by Formula VIII:

[0277] [ka] is conjugated via a linker of the formula: n is 0, 1, 2, 3, or 4; R1 is selected from a 6- to 14-membered aryl or a 5- to 10-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —C(O)NH2, —C(O)OR6, —C 1-3 selected from alkyl, -OR7, and 6- to 10-membered aryl; R6 is hydrogen or C 1-3 is alkyl, R7 is hydrogen or C 1-3 is alkyl, R2 is absent or selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R3 is hydrogen or -C1-C5COOH; R4 is -C 1-10 Alkyl-, -C 2-6 Alkenyl-, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl-N(R8)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, -N(R8)-C 2-6 Alkyl-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl-(-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, A binds to NH via its C-terminus, R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , and -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from R 19 But hydrogen, -C 1-3 Alkyl or -C 1-3 Alkyl-OC 1-3 alkyl-OH; R 20is hydrogen or -C 1-3 is alkyl, R 21 is hydrogen or -C1-3 alkyl, Het2 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , or -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0278] [ka] is selected from R 15 is hydrogen or C1-C3 alkyl, R 16 is hydrogen or C1-C3 alkyl, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3substituted with alkyl, halogen, or -OH; R 17 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 18 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , or -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 , or

[0279] [ka] is selected from R 25 is hydrogen or C1-C3 alkyl, R 26 is hydrogen or C1-C3 alkyl, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 Ligand-drug conjugates are provided that are substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2.

[0280] According to one embodiment of the present invention, A is an amino acid or a peptide comprising two or more of the same or different amino acids. A is as defined in the first aspect.

[0281] According to one embodiment, L is an antigen-binding ligand. According to a preferred embodiment, the ligand is a prostate-specific membrane antigen (PSMA)-binding ligand.

[0282] According to one embodiment, L is a ligand of formula L1.

[0283] In one embodiment, t1 is 3, t2 is 2, Z is N(R9), and R9 is hydrogen. In one embodiment, t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl. In another embodiment, t1 is 3, t2 is 2, Z is N(R9), and R9 is phenyl substituted with Cl, Br, or I. In one embodiment, t1 is 0, t2 is 2, Z is Z1, and t3 is 1, 2, 3, 4, 5, or 6, and Y is -NH-. In one embodiment, t1 is 1, t2 is 2, and Z is a compound of formula Z2.

[0284] In one embodiment, the compound is of formula VIII, wherein R 11 but, * -CH2OC(O)- ** ,

[0285] [ka] is selected from.

[0286] In one embodiment, the compound is of formula VIII, wherein R 13 is hydrogen and R 14 But -C 1-5 Alkyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-5 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , or -C 1-3Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0287] [ka] is selected from R 15 is selected from H, —CH3, or —C2H5; R 16 is selected from H, —CH3, or —C2H5; R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 17 is selected from hydrogen or —C(O)NH—C2H5—N(CH3)2, R 18 is selected from hydrogen or —C(O)NH—C2H5—N(CH3)2, Het3 is triazolyl, In one embodiment, the compound is of formula VIII, wherein R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 It is substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2.

[0288] In one embodiment, the compound is a compound of formula VIII, wherein R 23 is hydrogen and R 24 But -C 1-5 Alkyl, -C 1-5 Alkyl-N(R25 )(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-5 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , or -C 1-3 Alkyl-Het4-(-C2H4O) 1-10 -C2H4-R 28 , or

[0289] [ka] is selected from R 25 is selected from H, —CH3, or —C2H5; R 26 is selected from H, —CH3, or —C2H5; or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is selected from hydrogen or —C(O)NH—C2H5—N(CH3)2, R 28 is selected from hydrogen or —C(O)NH—C2H5—N(CH3)2, Het4 is triazolyl, In one embodiment, the compound is of formula VIII, wherein R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3It is substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2.

[0290] According to one embodiment of the present invention, D is an active ingredient having a cytotoxic or therapeutic effect as defined above.

[0291] According to one embodiment, the present invention provides a compound of formula VIII, wherein: n is 0, 1, or 2; R1 is selected from a 6- to 10-membered aryl or a 5- to 10-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R1 is unsubstituted or substituted with one or more R5; R5, at each occurrence, is independently selected from halogen, —OH, —OCH3, —OC2H5, or 6- to 10-membered aryl; R2 is selected from the group consisting of 5- to 6-membered cycloalkyl and 6- to 10-membered aryl; R3 is hydrogen; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 -Alkyl-N(H)-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2 alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is cit, ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-phe-gly, gly-gly-phe-gly, formula P3, formula P5, formula P9, formula P 12 , formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of:

[0292] According to one embodiment, the present invention provides a compound of formula VIII, wherein: n is 1, R1 is naphthyl, R2 is cyclohexyl or phenyl; R3 is hydrogen; R4 is -C 1-10 Alkyl, -C 2-6 Alkenyl, -C 1-3 Alkyl-OC 1-3 Alkyl-, -C 2-6 Alkyl(N(R8)(R 8’ ))-, 3- to 6-membered cycloalkyl, and -C 1-2 Alkyl (-OC2H4) 1-8 -OC 1-2 alkyl-, R8 and R 8’ are independently hydrogen, C 1-6 Alkyl, -C(O)-C 1-4 Alkyl-aryl, or -C(O)-(-C2H4O) 1-8 -C 1-2alkyl-N(R)(R'), wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; R and R' are independently hydrogen, -C 1-6 Alkyl, or -C(O)-C 1-4 alkyl-aryl, wherein the aryl is selected from 6- to 14-membered aryl; 1-3 Alkyl or -OC 1-3 optionally substituted with alkyl; A is cit, ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-phe-gly, gly-gly-phe-gly, formula P3, formula P5, formula P9, formula P 12 , formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of R 11 But -C 1-3 Alkyl-OC(O)- ** , -C 1-3 Alkyl-OC(O)-N(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- ** , -C 1-3 Alkyl-OC(O)-N[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- ** , or -C 1-3 Alkyl-OC(O)-Het2-C 1-3 Alkyl-N(R 19 )-C(O)- ** is selected from R 19is selected from H, CH, or —C2H4—O—C2H4—OH; R 20 is CH3 and R 21 is CH3, Het2 is pyrrolidinyl, R 12 is hydrogen, -C(O)N(R 13 )(R 14 ), or -(-OC2H4) 1-10 -CH3, R 13 is hydrogen, R 14 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 15 )(R 16 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 17 , or -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 18 , or

[0293] [ka] is selected from R 15 is -CH3 or -C2H5, and R 16 is -CH3 or -C2H5, or R 15 and R 16 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or substituted with -CH3; R 17is -C(O)NHC2H4N(CH3)2, R 18 is -C(O)NHC2H4N(CH3)2, Het3 is triazolyl, or R 13 and R 14 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2; R 22 is hydrogen, -C(O)N(R 23 )(R 24 ), or -(-OC2H4) 1-10 -CH3, R 23 is hydrogen, R 24 But -C 1-5 Alkyl, -C 2-5 Alkenyl, -C 2-5 Alkynyl, -C 1-5 Alkyl-N(R 25 )(R 26 ), -C 1-5 Alkyl-OC 1-3 Alkyl, -(-C2H4O) 1-10 C2H5, -(-C2H4O) 1-10 -C2H4-R 27 , or -C 1-3 Alkyl-Het3-(-C2H4O) 1-10 -C2H4-R 28 , or

[0294] [ka] is selected from R 25 is hydrogen or C1-C3 alkyl, R 26is hydrogen or C1-C3 alkyl, or R 25 and R 26 together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, in which one or two carbon atoms in the heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and the 5- to 6-membered heterocyclyl ring is unsubstituted or 1-3 substituted with alkyl, halogen, or -OH; R 27 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; R 28 is hydrogen or -C(O)NH-C 2-5 alkyl-N(CH3)2; Het3 is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R 23 and R 24 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in the heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and the 4- to 6-membered heterocyclyl ring is unsubstituted or 1-3 It is substituted with alkyl, -N(CH3)2, or -CH2N(CH3)2.

[0295] According to one embodiment, the present invention provides a compound of formula VIII, wherein: R4 is -C 2-5 selected from the group consisting of alkyl, -CH=CH-, -CH-O-CH-, -CH(-OCH)-OCH-, and cyclobutyl; A is selected from the group consisting of cit, val-ala, val-cit, gly-gly-phe-gly, or the peptide is selected from the group consisting of formula P3, formula P5, formula P9, formula P 12 , formula P 13 , formula P 14 , formula P 15, and the formula P 16 is selected from the group consisting of:

[0296] In one embodiment, the present invention provides a compound of formula VIII, wherein: R4 is -C 2-5 selected from the group consisting of alkyl and 3- to 6-membered cycloalkyl; A is cit, val-ala, val-cit, glu-val-cit, gly-gly-phe-gly, formula P1, formula P 13 , formula P 14 , formula P 15 , and the formula P 16 is selected from the group consisting of:

[0297] According to another embodiment, the present invention provides a compound of formula VIII, wherein: n is 0, 1, or 2; R1 is selected from the group consisting of phenyl, indolyl, thiophenyl, quinolinyl, and isoquinolinyl; R1 is unsubstituted or substituted with one or more R5; R5, in each occurrence, is independently selected from halogen, —OH, or a 6- to 10-membered aryl ring; R2 is cyclohexyl or phenyl; R3 is hydrogen; R4 is -C 1-10 is alkyl, A is val-cit, R 11 is -CH2OC(O)-, and R 12 is hydrogen and R 22 is hydrogen.

[0298] According to one embodiment, the present invention provides a compound of formula VIII, wherein: n is 0, 1, or 2; R1 is a 6- to 10-membered aryl; R2 does not exist, R3 is -CH2COOH, -CH2CH2COOH, R4 is a 3- to 6-membered cycloalkyl; A is Cit, R 11 is -CH2-OC(O)-N(CH3)-C2H4-N(CH3)-C(O)-, R 12 is hydrogen and R 22 is hydrogen.

[0299] In another aspect, the present disclosure provides a compound of formula VIII:

[0300] [ka] or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R1,

[0301] [ka] is selected from n is selected from 0, 1, and 2; R2 is not present, or

[0302] [ka] is selected from R3 is selected from hydrogen and —C2H4COOH; R4,

[0303] [ka] , -C 2-5 Alkyl, -CH=CH-, -CH2-O-CH2-, -CH2(-OC2H4) 2-8 -OCH2-,

[0304] [ka] is selected from A is selected from cit, val-cit, val-ala, gly-gly-phe-gly, glu-val-cit, gly-gly-phe, gly-phe-gly, Formula P1-ala, Formula P3, Formula P4-ala, Formula P5, Formula P9, Formula P12, Formula P13, and Formula P16;

[0305] [ka] but,

[0306] [ka]

[0307] [ka] is selected from D is a cytotoxic or therapeutic agent selected from monomethyl auristatin E (MMAE), rucaparib, talazoparib, niraparib, SN-38, exatecan, belotecan, mitomycin C, and the like, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0308] In one embodiment, the present disclosure relates to a compound of formula II, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: R1,

[0309] [ka] and n is 1, R2,

[0310] [ka] and R3 is hydrogen; R4 is -C3H6-, A is val-cit,

[0311] [ka] but,

[0312] [ka] and D is monomethyl auristatin E (MMAE).

[0313] Some examples of compounds of the present invention are shown in Table 1 below. Those skilled in the art will understand that the compounds listed in Table 1 are limited, and that those skilled in the art can obtain several such compounds depending on the definitions of the variables in the above embodiments. All such compounds envisioned by those skilled in the art are included in the present invention. Furthermore, whenever the IUPAC name and structure of a compound are mentioned herein, the structure shall take precedence over the name. Any errors in the IUPAC name are unintentional.

[0314] [Table 1-1]

[0315] [Table 1-2]

[0316] [Table 1-3]

[0317] [Table 1-4]

[0318] [Table 1-5]

[0319] Table 1-6

[0320] Table 1-7

[0321] Table 1-8

[0322] Table 1-9

[0323] Table 1-10

[0324] Table 1-11

[0325] Table 1-12

[0326] Table 1-13

[0327] Table 1-14

[0328] Table 1-15

[0329] Table 1-16

[0330] Table 1-17

[0331] Table 1-18

[0332] Table 1-19

[0333] Table 1-20

[0334] Table 1-21

[0335] Table 1-22

[0336] Table 1-23

[0337] Table 1-24

[0338] Table 1-25

[0339] Table 1-26

[0340] Table 1-27

[0341] Table 1-28

[0342] Table 1-29

[0343] Table 1-30

[0344] Table 1-31

[0345] Table 1-32

[0346] Table 1-33

[0347] Table 1-34

[0348] Table 1-35

[0349] Table 1-36

[0350] Treatment method The compounds of the present invention have been found to have affinity for PSMA-expressing cells. The ability of the compounds of the present invention to selectively inhibit PSMA-expressing cells was tested in vitro in PSMA-expressing human prostate cancer (PC3)-PIP cells compared to PSMA-negative PC3 flu cells. The following table (Table 2) shows the inhibitory concentrations (IC) required to exhibit half-maximal responses for inhibiting PSMA-expressing PC3 PIP cells and PSMA-negative PC3 flu cells by the compounds of the present invention. 50 ) is shown.

[0351] [Table 2]

[0352] As can be seen from Table 2, the inhibitory concentrations (IC 50 ) was significantly lower than that for PC3 flu cells. For almost all compounds, the IC 50 The IC of PC3 PIP was over 100-fold lower than that of PC3 flu. 50 The IC of PC3 PIP was over 200-fold lower than that of PC3 flu cells. 50 The IC of PC3 PIP for compound 1.4 was 300-fold lower than that for PC3 flu cells. 50 The IC of PC3 PIP for compound number 1.5 was 690-fold lower than that of PC3 flu. 50 The IC of PC3 PIP cells was 8935-fold lower than that of PC3 flu, demonstrating that the compounds of the present invention are highly selective for inhibiting PSMA-expressing cells compared to PSMA-negative cells. Furthermore, the IC of PC3 PIP cells was 8935-fold lower than that of PC3 flu. 50 The IC value was quite low, indicating that the compounds exhibited high cytotoxicity even at very low concentrations. In particular, compound No. 1.16 had an IC of 0.054 nM. 50Similarly, compounds 1.5, 1.7, and 1.10 also showed IC values ​​of less than 0.2 nM, indicating very high efficacy. 50 The results show that the compound of the present invention is highly selective and effective in the cytotoxicity of the cells that express PSMA.Therefore, it is believed that the compound of the present invention provides an option for the treatment of diseases that are related to the cells that express PSMA.

[0353] Cell viability assay to evaluate the antiproliferative effect of NCEs on the proliferation of LNCaPWT and LNCaP-PSMA- / - cells: Cell lines were cultured in RPMI-1640 (HiMedia) containing 10% FBS (Gibco), 100 U / ml penicillin, 0.1 mg / ml streptomycin, and 0.25 μg / ml amphoteresin B. Cells were maintained in a humidified atmosphere at 37°C and 5% CO .

[0354] Cells were seeded at optimal density in 96- or 384-well plates in RPMI-1640 medium supplemented with 10% FBS. After 24 hours, cells were treated with various concentrations of compounds or vehicle. The final DMSO concentration was maintained at 0.5%. Treated cells were incubated for 96 hours, after which cell viability was measured using a Cell Titer Glo luminescence assay (Promega, USA). Briefly, plates were equilibrated at room temperature for 30 minutes. 75 μl / well of Cell Titer Glo was added, and the plate was mixed on an orbital shaker for 4 minutes to induce cell lysis, followed by incubation at room temperature for 10 minutes. Luminescence values ​​were recorded, and cell viability was measured as the percentage of growth inhibition relative to the vehicle control (0.5% DMSO). IC of compounds 50 was calculated using statistical analysis of Log(inhibitor) vs. % growth inhibition - variable slope (four parameters) using GraphPad Prism software.

[0355] [Table 3]

[0356] In one aspect of the present invention, a method for treating a disease is provided. According to another aspect, the present invention provides a method for treating a disease associated with PSMA expression. According to a specific aspect, the present invention provides a method for treating cancer. According to another specific aspect, the present invention provides a method for treating cancer associated with PSMA expression.

[0357] PSMA is a membrane antigen expressed in all types of prostate tissue. Expression is significantly enhanced in prostate cancer tissue compared to normal tissue. Apart from prostate tissue, PSMA is expressed in other cancer cells, such as conventional renal cells, bladder transitional cells, testicular-germ, neuroendocrine, colon, and breast cancer cells. Specifically, PSMA is expressed in the neovasculature of solid tumors. In one embodiment, the present invention provides a method for treating all such solid tumors or cancers associated with PSMA-expressing cells. Non-limiting examples of such cancers include prostate cancer, lung cancer, renal cell carcinoma, glioblastoma, pancreatic cancer, bladder cancer, breast cancer, colon cancer, esophageal cancer, gastric cancer, head cancer, neck cancer, head and neck cancer, colorectal cancer, leukemia / lymphoma, uterine cancer, skin cancer, endocrine cancer, urinary cancer, gastrointestinal cancer, ovarian cancer, and cervical cancer.

[0358] In one embodiment, the present invention also provides methods for treating certain benign lesions that arise in PSMA-expressing tissue cells, such as conventional renal cells, transitional cells of the bladder, testicular-germ, neuroendocrine, colon, and breast cells.

[0359] According to one aspect of the present invention, there is provided a method for treating a disease, the method comprising administering a compound of the present invention to a subject in need thereof. In one embodiment, the method comprises administering to the subject a compound of Formula I, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof. In one embodiment, the method comprises administering to the subject a compound of Formula II, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof. In one embodiment, the method comprises administering to the subject a compound of Formula III, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof. In one embodiment, the method comprises administering to the subject a compound of Formula IV, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof. In one embodiment, the method comprises administering to the subject a compound of Formula V, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof. In one embodiment, the method comprises administering to the subject a compound of Formula VI, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof. In one embodiment, the method comprises administering to the subject a compound of formula VII, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0360] Those skilled in the art will appreciate that the method involves administering a therapeutically effective amount of a compound of the present invention, which will depend on several factors, including, but not limited to, the type and stage of the disease, the sex and age of the subject, the method of administration of the compound (e.g., oral, parenteral, subcutaneous), and the composition of the compound.

[0361] According to one aspect of the present invention, there is provided a method of treating a disease, comprising administering to a subject in need thereof a therapeutically effective amount of a compound selected from the group consisting of a compound of formula I, a compound of formula II, a compound of formula III, a compound of formula IV, a compound of formula V, a compound of formula VI, a compound of formula VII, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof.

[0362] Pharmaceutical Compositions Any of the compounds disclosed herein can be formulated into a composition further comprising one or more suitable pharmaceutically acceptable excipients, including carriers and other compounds that facilitate administration of the compound to a subject. Pharmaceutical compositions can be formulated in a conventional manner using one or more pharmaceutically acceptable excipients. Such pharmaceutical compositions and methods for their preparation are described, for example, in Remington: The Science and Practice of Pharmacy, the contents of which are incorporated herein by reference in their entirety.

[0363] Thus, in one embodiment, the present invention provides a pharmaceutical composition comprising a compound of Formula I, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a pharmaceutical composition comprising a compound of Formula II, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a pharmaceutical composition comprising a compound of Formula III, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a pharmaceutical composition comprising a compound of Formula IV, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a pharmaceutical composition comprising a compound of Formula V, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a pharmaceutical composition comprising a compound of formula VI, or a pharmaceutically acceptable salt, or stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a pharmaceutical composition comprising a compound of formula VII, or a pharmaceutically acceptable salt, or stereoisomer, or isotope thereof, and a pharmaceutical excipient.

[0364] Suitable doses of the compounds for use in treating any of the diseases, disorders, and / or conditions described herein can be determined by those skilled in the art. The dose must be sufficient to provide the desired therapeutic benefit without causing undesirable side effects. Modes of administration, dosage forms, and suitable pharmaceutical excipients are also understood and within the knowledge of those skilled in the art.

[0365] In one embodiment, the present invention provides a method for treating a cancer that is positive for PSMA expression, comprising administering a pharmaceutical composition comprising a compound of Formula I, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a method for treating a cancer that is positive for PSMA expression, comprising administering a pharmaceutical composition comprising a compound of Formula II, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a method for treating a cancer that is positive for PSMA expression, comprising administering a pharmaceutical composition comprising a compound of Formula III, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a method for treating a cancer that is positive for PSMA expression, comprising administering a pharmaceutical composition comprising a compound of Formula IV, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a method for treating a cancer that is positive for PSMA expression, comprising administering a pharmaceutical composition comprising a compound of Formula V, or a pharmaceutically acceptable salt, or stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a method for treating a cancer that is positive for PSMA expression, comprising administering a pharmaceutical composition comprising a compound of Formula VI, or a pharmaceutically acceptable salt, or stereoisomer, or isotope thereof, and a pharmaceutical excipient. In one embodiment, the present invention provides a method for treating a cancer that is positive for PSMA expression, comprising administering a pharmaceutical composition comprising a compound of Formula VII, or a pharmaceutically acceptable salt, or stereoisomer, or isotope thereof, and a pharmaceutical excipient.

[0366] The pharmaceutical compositions of the present invention may be formulated as, for example, a tablet, capsule, liquid, gel, syrup, suspension, or slurry. Excipients may be selected from those known in the art.

[0367] Administration according to the present invention can be carried out by routes known to those skilled in the art, non-limiting examples of which are oral administration, intravenous, intramuscular, intraperitoneal, intrathecal, or subcutaneous injection; rectal administration; intranasal administration, ocular administration, or topical administration.

[0368] In one embodiment, there is provided a use of a compound of the invention for the treatment of a cancer that is positive for PSMA expression. In another embodiment, there is provided a use of a compound of the invention in the preparation of a medicament for use in the treatment of a cancer that is positive for PSMA expression.

[0369] General method of preparation The compounds of the present invention can be prepared by methods involving several steps, including coupling reactions, protection and deprotection, oxidation, reduction, addition, elimination, and other reactions well known to those skilled in the art. Furthermore, these steps can be carried out using known methods, such as those documented in Richard C. Larock, Comprehensive Organic Transformations; Peter G.M.Wuts, Greene's Protective Groups in Organic Synthesis; George R. Petit, Synthetic Peptides; M. Bodanszky, Principles of Peptide Synthesis; James Ralph Hanson, Protecting Groups in Organic Synthesis; Michael B. Smith, March's Advanced Organic Chemistry (2019); E. Gross, The Peptides: Analysis, Synthesis, Biology; J.F.W. McOmie, Protective Groups in Organic Chemistry; and N. Leo Benoiton, Chemistry of Peptide Synthesis.

[0370] Any variation from the methods reported in the above literature is within the knowledge of one skilled in the art.

[0371] The compounds of the present invention and their intermediates can be separated from the reaction mixture and purified using methods known in the art. Some non-limiting examples of separation methods are filtration, distillation of solvents, liquid-liquid extraction and phase separation, or centrifugation, and / or decantation. Some separation methods may involve purification steps such as treatment with acid and / or base, or carbon. Chiral compounds and their chiral intermediates can optionally be separated as their enantiomers and / or diastereomers by known methods, such as those described in N.L. Allinger Topics in Stereochemistry, Ganapathy Subramanian, Chiral Separation Techniques: A Practical Approach. One possible method for enantiomer separation is the use of chromatography.

[0372] Purification methods for the compounds of the present invention and their intermediates may include acid-base or base-acid treatment, distillation, filtration, and solvent treatment, as well as chromatographic purification methods such as column chromatography and preparative chromatography. The above separation and purification methods are exemplary and may vary depending on the nature of the product being separated. Such variations are well within the understanding of one of ordinary skill in the art.

[0373] One method for preparing the compounds of the present invention is described below. However, modifications and transformations from the specific method are well within the knowledge of one skilled in the art, and one skilled in the art can envision that the compounds can be prepared by several other methods using different starting materials, reagents, and conditions.

[0374] Compounds of formula I can be prepared according to Scheme 1, wherein L, m, R1, R2, R3, R4, A, Q, and D are as defined above.

[0375] [ka]

[0376] AG1 is an activating group. An "activating group" is a group that, when reacted with a target functional group, generates a group that is selectively reactive under certain conditions and stable under other conditions. For example, in formula IX in scheme 1, AG1 is an activating group that reacts with the -COOH functional group moiety to generate a compound such as an ester. Under certain other conditions, this ester may remain stable, but when it reacts with a compound of formula X, it easily forms an amide bond with A. Those skilled in the art are well aware of various activating groups, their selection criteria, and their use in the preparation process of a specific product.

[0377] For example, to make a carboxyl group (-COOH) active against a specific reagent, it can be converted into an ester or acid chloride. To prepare such compounds, the carboxyl group is reacted with a precursor of an activating group, where those skilled in the art have knowledge of the selection of a precursor of an activating group and the reaction conditions under which such a precursor of an activating group can be converted into an activated carboxyl group. Non-limiting examples of precursors of an activating group include N-hydroxysuccinimide, pentafluorophenol, or those listed in Vincent Gembus et al., Maciej Adamczyk et al., or Yoon-Sik Lee et al.

[0378] Those skilled in the art will understand that under certain conditions, an activating group can also act as a protecting group, preventing the functional moiety to which it is attached from reacting, but allowing the same functional moiety without this particular activating or protecting group to react and be converted into another functional moiety. The differences between activating and protecting groups, the factors involved in selecting either one of these groups, and the conditions under which such groups are used in reactions are within the knowledge of those skilled in the art.

[0379] A "protecting group," as the name suggests, is a group used to hide a functional group that is at risk of reacting in a particular medium or being converted to some other form in a series of reactions. When removed (deprotection of the functional group), the protecting group yields the functional moiety or group that was present prior to protection.

[0380] In one embodiment, the present invention relates to compounds formed by the protection and deprotection of their precursors. In another embodiment, the present invention relates to compounds formed by the protection and deprotection of intermediates involved in the preparation of the compounds of the present invention. Such compounds include amino-protected intermediates and carboxyl-protected intermediates.

[0381] In the present invention, functional groups that are particularly protected are carboxyl groups and amino groups (both primary and secondary). Suitable protecting groups for different functional groups can be selected as described, for example, in Peter G.M.Wuts, Greene's Protective Groups in Organic Synthesis (Fifth Edition, 2014), Pathalk et al., Yong-qian Wu et al., James Ralph Hanson, Protecting Groups in Organic Synthesis, E. Gross, The Peptides: Analysis, Synthesis, Biology, J.F.W.M.C.Omie, Protective Groups in Organic Chemistry, and N. Leo Benoiton, Chemistry of peptide synthesis.

[0382] Examples of protecting groups for hydroxyl or carboxyl groups include, but are not limited to, benzyl, p-methoxybenzyl (PMB), tert-butyl (t-Bu), methoxymethyl (MOM), methoxyethoxymethyl (MEM), methylthiomethyl (MTM), tetrahydropyranyl (THP), tetrahydrofuranyl (THF), benzyloxymethyl (BOM), trimethylsilyl (TMS), triethylsilyl (TES), tert-butyldimethylsilyl (TBDMS), and triphenylmethyl (trityl, Tr). Similarly, specific examples of protecting groups for amino groups include, but are not limited to, tert-butylcarbonyloxy (Boc), fluorenylmethyocycarbonyl (Fmoc), benzyloxycarbonyl (Cbz), allyloxycarbonyl (Alloc), benzyl, p-methoxybenzyl (PMB), triphenylmethyl (trityl, Tr), trifluoroacetamide, acetyl (Ac), and benzylidene.

[0383] According to Scheme 1, compounds of formula IX and formula X can be condensed to form a compound of formula I. The condensation can be carried out by combining both compounds of formula IX and formula X in the presence or absence of a base, including organic bases such as triethylamine, N,N-diisopropylethylamine, N-methylmorpholine, and 4-(dimethylamino)piperidine (DMAP), and inorganic bases such as sodium bicarbonate or potassium carbonate, preferably in the presence of a base. In the condensation of compounds of formula IX and formula X, a solvent may optionally be used. Non-limiting examples of such solvents include N,N-dimethylformamide (DMF), tetrahydrofuran (THF), 1,4-dioxane, dimethyl sulfoxide, acetonitrile, and N,N-dimethylacetamide. Furthermore, reaction conditions such as temperature, pressure, or time are variables and will depend on and vary accordingly for different definitions of L, m, R1, R2, R3, R4, AG1, A, Q, and D. The final product can be isolated and purified by the methods described above.

[0384] According to one embodiment of the present invention, compounds of formula I are prepared using the corresponding precursors of formula IX and formula X by reacting them together in the presence of a base selected from N,N-diisopropylethylamine or trimethylamine, triethylamine (TEA) and N,N-dimethylformamide (DMF).

[0385] The compounds of the present invention include their intermediates, which may have one or more chiral centers. All possible chiral isomers (or optical isomers or stereoisomers) formed due to the presence of a chiral center / multiple chiral centers in the compounds and their intermediates are fully within the scope of the present invention. Such compounds can be prepared as optically active or racemic compounds. Processes for preparing either of the two forms (optically active or racemic) are well known in the art. Those skilled in the art can predict all optical isomers of each compound and can prepare each optical isomer using known methods. For example, optical isomers of compounds of Formula I can be prepared by resolution from a chiral mixture, asymmetric synthesis, or synthesis from optically active starting materials. Resolution of racemates can be achieved by conventional methods, such as crystallization in the presence of a resolving agent or chromatography using, for example, a chiral HPLC column.

[0386] Furthermore, the compounds of the present invention may exhibit geometric isomerism in the presence of olefins, C=N double bonds, etc. According to one embodiment, the present invention relates to all such isomers, including but not limited to cis and trans geometric isomers, E and Z isomers, or mixtures of isomers, or zwitterionic forms. These isomers may be prepared and separated by methods well known in the art.

[0387] The pharmaceutically acceptable salts of the present invention can be synthesized from parent compounds containing a basic or acidic moiety by conventional chemical methods. Generally, such salts can be prepared by reacting the free acid form of these compounds with a stoichiometric amount of an appropriate base, or by reacting the free base form of these compounds with a stoichiometric amount of an appropriate acid. Such reactions are typically carried out in a solvent such as water, ether, ethyl acetate, ethanol, isopropanol, acetonitrile, N,N-dimethylformamide, dimethyl sulfoxide, or a mixture of one or more such solvents.

[0388] It is within the knowledge of one skilled in the art to access intermediates of formula IX and formula X. Furthermore, one skilled in the art would also understand how to access these intermediates using different variables of L, m, R1, R2, R3, R4, AG1, A, Q, and D. Retrosynthesis of a compound of formula IX will yield more than one possible way to prepare it. As can be seen in Figure 1 below, there are several fragments that can be used in different combinations to prepare a compound of formula IX.

[0389] [ka]

[0390] symbol

[0391] [ka] A bond marked with a ☐ indicates that it can be formed by condensing or coupling the fragment to its right with the fragment to its left.

[0392] It is within the knowledge of one skilled in the art to select the preferred fragments, prepare the intermediates and arrive at the compound of formula IX in due course.

[0393] For example, according to one method, a compound of formula IX can be prepared from a compound of formula XI (Scheme 2), where R1, R2, and R3 are as defined above. p is a protected L, where one or more, or sometimes all, -COOH groups in L may be protected as an ester.

[0394] [ka]

[0395] Compounds of formula IX can be prepared by reacting compounds of formula XI with a precursor of R4. For example, compounds of formula XI are

[0396] [ka]

[0397] wherein LG1 and LG2 are -OH or leaving groups. It is within the knowledge of a person skilled in the art to appropriately select a leaving group according to the purpose for which it is needed. For example, the leaving group can be a halogen selected from F, Cl, or Br, or it can be a group such as N-hydroxysuccinimide, 1-hydroxybenztriazole (HOBt), or pentafluorophenol.

[0398] PG1 and PG2 are the same or different protecting groups. Those skilled in the art will have the knowledge and understanding to convert the intermediate formed by the reaction between formula XI and the precursor of R4 to a compound of formula IX. This may involve deprotection by removal of the protecting group, followed by reaction with a suitable reagent containing an activating group. Alternatively, the protecting groups PG1 and PG2 may be directly replaced with AG1. L p The deprotection of can be carried out simultaneously with the deprotection of PG1 or PG2 or sequentially, depending on the methods considered feasible by the skilled artisan.

[0399] The compound of formula XI is L p The compound of formula XI can be prepared by a coupling reaction between fragment 1, fragment 2, and fragment 3. Since fragment 1 and fragment 2 can be considered as unconventional amino acids before being coupled together, the synthesis of the compound of formula XI can be carried out by known methods in peptide synthesis, such as those disclosed by N. Leo Benoiton, "Chemistry of Peptide Synthesis," and M. Bodanszky, "Principles of peptide synthesis." Those skilled in the art will appreciate that the synthesis of the compound of formula XI can be carried out by known methods in peptide synthesis, such as those disclosed by N. Leo Benoiton, "Chemistry of Peptide Synthesis," and M. Bodanszky, "Principles of peptide synthesis." pThe combination of fragment 1 and fragment 2 can be sequential or random, where fragment 1 and fragment 2 are first coupled and the resulting peptide is then L p It will be understood that fragment 1 and fragment 2 can be coupled to one another. Fragment 1 and fragment 2 are commercially available or can be prepared according to methods known in the art. p can be prepared by protecting a compound of formula L1, which may be commercially available or can be prepared according to methods known in the art or methods disclosed in Sung-Hyun Moon et al., or Michael Felber et al. Compounds of formula L1, where Z is of formula Z1 or Z2, can be prepared by reacting a compound of formula L2 or L3, respectively, with a substituted maleimide compound or a diamine compound.

[0400] [ka]

[0401] The choice of compound of formula L2 or L3 and maleimide or diamine compound will depend on the target compound of formula L1, and is within the understanding of one skilled in the art.

[0402] The compound of formula X includes A, Q, and D. Each A, Q, and D is a different moiety that may require independent preparation before combining them together. In some methods, the compound of formula X can be prepared sequentially from A to D. In some other methods, A or a precursor thereof can be combined with fragment 4 of Figure 1 to form an amide, and then the compound of formula I can be constructed stepwise.

[0403] For example, in one method, compounds of formula X can be prepared as shown below (Scheme 3):

[0404] [ka] In the formula, A p is protected A, and AG2 is an activating group. The free N-terminus of A can be protected as an N-alkyl, amide, or carbamate, and the group can be activated with Q to form a carbonate. The reaction between the compound of formula XII and D can be carried out in the presence of a catalyst such as 1-hydroxybenzothyrazole (HOBt), or the catalysts disclosed by Yanming Wang et al. and Stephen J. Walsh et al., and a base such as N,N-diisopropylethylamine, triethylamine, or pyridine. The compound of formula XIII prepared as an intermediate can be deprotected in an acidic or basic medium, preferably in the presence of a catalyst, to give the compound of formula X.

[0405] A and Q are commercially available or can be prepared by known methods. When A is a peptide, it can be prepared by methods known in the art or by methods disclosed in M. Bodanszky "Principles of Peptide Synthesis", N. Leo Benoiton "Chemistry of Peptide Synthesis", or Deboprosad Mondal et al.

[0406] Formula P1~P 12 For peptides such as: NH2 can be reacted with an appropriate polyethylene glycol derivative while protecting other reactive sites. NH2 can be activated using an activating group prior to such reaction.

[0407] Alternatively, compounds of formula X can be prepared according to Scheme 4 below:

[0408] [ka] where AG3 is an activating group that can be the same as or different from AG2. 11A -C 1-3 alkyl-OC(O)-, and R11B teeth, HN(R 19 )-C 1-5 Alkyl-N(R 19 )-C(O)- * , HN[C 1-5 Alkyl-N(R 20 R 21 )]-C 1-3 Alkyl- * , and Het2-C 1-3 Alkyl-N(R 19 )-C(O)- * and R 19 , R 20 , R 21 , and Het2 are as defined above.

[0409] Compounds of the present invention may also include all isotopes of atoms occurring in the intermediates or final compounds. Isotopes include atoms having the same atomic number but different mass numbers. For example, isotopes of hydrogen include tritium and deuterium.

[0410] Such compounds can be synthesized by means well known in the art, for example, by utilizing starting materials in which one or more hydrogen atoms have been replaced with deuterium. Deuterated analogs can improve drug metabolism and pharmacokinetic properties; see, e.g., Allan B. Foster et al.

[0411] All of the above methods are for illustrative purposes. For a more detailed description of the preparation of the compounds of the present invention, along with details of the individual reaction steps, please see the Examples section set forth below. While specific starting materials and reagents are set forth in the Examples section, other starting materials and reagents can be readily substituted to provide a variety of derivatives and / or reaction conditions. In addition, many of the compounds prepared by the methods described below can be further modified in light of this disclosure using methods known to those skilled in the art. The examples set forth below are for illustrative purposes. These examples are non-binding and do not limit or restrict the scope of the invention in any way. [Example]

[0412] The final products of the present invention were identified using mass spectrometry (manufacturer: Waters, model: Quattro premier, software: Masslynx V4.1, SCN80). Preparative HPLC (manufacturer: Shimadzu, model: Prominence) was used in some examples.

[0413] Abbreviation: EDAC - 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride EEDQ- N-Ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline MDC / DCM - Dichromethane DIPEA- N,N-diisopropylethylamine DMF - N,N-dimethylformamide DMAP- 4-dimethylaminopyridine HATU- 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluoro phosphate HCl - Hydrochloric acid HOBt - 1-Hydroxybenzotriazole HPLC - High Performance Liquid Chromatography NaCl - Sodium chloride NHS- N-Hydroxysuccinimide RT - Room temperature TBTU- O-(Benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate THF - tetrahydrofuran TFA - Trifluoroacetic acid hr / h / hrs- Hours

[0414] Example 1: Preparation of Compound No. 1.4 Step I: Preparation of di-tert-butyl (2S)-2-[[(1S)-5-[[(2S)-2-(benzyloxycarbonylamino)-3-(2-naphthyl)propanoyl]amino]-1-tert-butoxycarbonyl-pentyl]carbamoylamino]pentanedioate (Formula 1c).

[0415] [ka]

[0416] TBTU (1.98 g, 6.2 mmol) and DIPEA (2.2 mL, 12.9 mmol) were added to a stirred solution of compound 1a (2.76 g, 5.7 mmol) and compound 1b (1.8 g, 5.2 mmol) in DMF (25 mL) at RT and stirred overnight. The reaction mixture was concentrated under reduced pressure at 50 °C, and the resulting crude product was purified by column chromatography (silica gel 230-400 mesh, DCM:methanol, 97:3) to give compound 1c.

[0417] Step II: Preparation of di-tert-butyl (2S)-2-[[(1S)-5-[[(2S)-2-amino-3-(2-naphthyl)propanoyl]amino]-1-tert-butoxycarbonyl-pentyl]carbamoylamino]pentanedioate (Formula 1d).

[0418] [ka]

[0419] To a stirred solution of the compound of formula 1c (4.7 g, 5.7 mmol) in methanol (50 mL) was added 10% palladium on carbon (50% wet) (0.5 g). The mixture was stirred under hydrogen pressure at RT for 6 hours. The reaction mixture was filtered through a Celite® bed and washed with methanol (2 × 50 mL). The combined filtrate was concentrated under reduced pressure to give the compound of formula 1d, which was used in the next step without purification.

[0420] Step III: Preparation of di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[4-[(9H-fluoren-9-ylmethoxycarbonylamino)methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate (Formula 1e).

[0421] [ka]

[0422] TBTU (2.16 g, 6.7 mmol) and DIPEA (2.3 mL, 12.9 mmol) were added to a stirred solution of the compound of formula 1d (3.55 g, 5.2 mmol) and 4-[(9H-fluoren-9-ylmethoxycarbonylamino)methyl]cyclohexanecarboxylic acid (2.55 g, 6.7 mmol) in DMF (35 mL) at RT and stirred overnight. The reaction mixture was concentrated under reduced pressure at 50° C. Water (150 mL) was added to the residue, and the resulting mixture was stirred at 55° C. for 1 hour. The resulting product was filtered, washed with water, and dried. The dried product was dissolved in a mixture of MDC and methanol, concentrated, and dried under reduced pressure at 50° C. to give compound of formula 1e.

[0423] Step IV: Preparation of di-tert-butyl (2S)-2-[[(1S)-5-[[(2S)-2-[[4-(aminomethyl)cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]-1-tert-butoxycarbonyl-pentyl]carbamoylamino]pentanedioate (Formula 1f).

[0424] [ka]

[0425] Piperidine (2.5 mL, 43.0 mmol) was added to a stirred solution of compound of formula 1e (9.0 g, 8.6 mmol) in DMF (90 mL) and stirred at RT for 1 h. The reaction mixture was concentrated under reduced pressure at 50 °C. Diethyl ether (10 mL) was added to the residue and stirred at RT for 30 min. The resulting product was filtered, washed with diethyl ether (2 × 10 mL), and dried under vacuum to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:aqueous ammonia, 83:15:2) to give compound of formula 1f.

[0426] Step V: Preparation of 5-[[4-[[(1S)-2-[[(5S)-6-tert-butoxy-5-[[(1S)-4-tert-butoxy-1-tert-butoxycarbonyl-4-oxo-butyl]carbamoylamino]-6-oxo-hexyl]amino]-1-(2-naphthylmethyl)-2-oxo-ethyl]carbamoyl]cyclohexyl]methylamino]-5-oxo-pentanoic acid (Formula 1g).

[0427] [ka]

[0428] DIPEA (0.32 mL, 1.8 mmol) was added to a stirred solution of the compound of formula 1f (1.0 g, 1.2 mmol) and glutaric anhydride (0.17 g, 1.5 mmol) in acetonitrile (10 mL) under a nitrogen atmosphere, followed by stirring at RT overnight. The reaction mixture was concentrated under reduced pressure at 40° C. Water (10 mL) was added to the residue, and the resulting mixture was acidified with aqueous citric acid (20% solution). The mixture was then extracted with ethyl acetate (3×30 mL). The combined organic layers were washed with brine solution and dried over anhydrous sodium sulfate. The ethyl acetate was removed under reduced pressure to give the compound of formula 1g, which was used in the next step without purification.

[0429] Step VI: Preparation of di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[4-[[[5-(2,5-dioxopyrrolidin-1-yl)oxy-5-oxo-pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate (Formula 1h).

[0430] [ka]

[0431] NHS (0.23 g, 1.8 mmol) and EDAC (0.38 g, 1.8 mmol) were added slowly to a stirred solution of the compound of formula 1g (1.0 g, 1.1 mmol) in DMF (10 mL) at RT and stirred overnight. The reaction mixture was quenched with water (10 mL) and extracted with ethyl acetate (3 x 20 mL). The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 40 °C to give the compound of formula 1h.

[0432] Step VII: Preparation of (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[5-(2,5-dioxopyrrolidin-1-yl)oxy-5-oxo-pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid (Formula 1i).

[0433] [ka]

[0434] TFA (5.5 mL) was added to a stirred solution of compound of formula 1h (0.55 g, 0.53 mmol) in DCM (5.5 mL) at 0-5°C. The reaction mixture was then stirred at RT for 6 h. Afterwards, the reaction mixture was concentrated and degassed under reduced pressure at 30°C. The crude product was extracted with diethyl ether (2 x 2 mL). The diethyl ether layer was decanted off and dried to give compound of formula 1i.

[0435] Step VIII: Preparation of {(S)-1-[(S)-1-(4-hydroxymethylphenylcarbamoyl)-4-ureidobutylcarbamoyl]-2-methylpropyl}carbamic acid allyl ester (Formula 1k).

[0436] [ka]

[0437] DIPEA (1.43 mL, 11 mmol) was added to a stirred solution of compound of formula 1j (2.1 g, 5 mmol) in a mixture of THF (21 mL) and DMF (5 mL). The reaction mixture was cooled to 0°C and 5°C, and allyl chloroformate (0.62 mL, 5.8 mmol) was added dropwise. The resulting mixture was stirred at 0°C and 5°C for 1 h. The mixture was concentrated under reduced pressure at 40°C, and water (20 mL) was added to the residue, which was extracted with ethyl acetate (3 × 50 mL). The combined extracts were washed with water (1 × 30 mL), followed by brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 50°C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol, 93:7) to give compound of formula 1k.

[0438] Step IX: Preparation of carbonic acid 4-[(S)-2-((S)-2-allyloxycarbonylamino-3-methylbutyrylamino)-5-ureido-pentanoylamino]benzyl 4-nitrophenyl ester (Formula 11).

[0439] [ka]

[0440] DIPEA (0.45 mL, 2.5 mmol) was added to a stirred solution of compound of formula 1k (0.6 g, 1.2 mmol) in DMF (6 mL) at RT. Bis(4-nitrophenyl)carbonate (0.6 g, 1.9 mmol) was added to the reaction mixture, and the resulting mixture was stirred for 3 h. The reaction mixture was concentrated under reduced pressure at 55 °C. Diethyl ether (5 mL) was added to the residue, which was leached and dried to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh, DCM:methanol, 93:7) to give compound of formula 1l (0.6 g).

[0441] Step X: Preparation of [4-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (Formula 1m)

[0442] [ka]

[0443] HOBt (57 mg, catalytic amount) and DIPEA (0.28 mL, 1.5 mmol) were added gradually to a stirred solution of compound of formula 1l (0.5 g, 0.8 mmol) and monomethyl auristatin E (0.57 g, 0.8 mmol) in DMF (5 mL) at RT and stirred for 30 h. The mixture was concentrated under reduced pressure at 55 °C. The resulting crude material was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol, 90:10) to give compound of formula 1m.

[0444] Step XI: Preparation of [4-[[(2S)-2-[[(2S)-2-amino-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methoxy-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (Formula 1n)

[0445] [ka]

[0446] Palladium tetrakis(triphenylphosphine) (0.065 g, 0.06 mmol) was added to a stirred solution of compound of formula 1m (0.9 g, 0.74 mmol) in a mixture of DCM (6.3 mL) and methanol (2.7 mL) at RT. Morpholine (0.45 mL, 5.2 mmol) was added to the mixture, and the mixture was stirred for 1.5 h. The reaction mixture was concentrated under reduced pressure at 35 °C. The crude material obtained was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol, 90:10) to give compound of formula 1n.

[0447] Step XII: Preparation of Compound No. 1.4

[0448] [ka]

[0449] DIPEA (0.096 mL, 0.55 mmol) was added to a stirred solution of the compound of formula 1n (0.076 g, 0.14 mmol) in DMF (1.25 mL), followed by the compound of formula 1i (0.125 g, 0.11 mmol) and stirred at RT for 24 h. The reaction mixture was concentrated under reduced pressure at 50 °C and degassed. DCM (5 mL) was added to the resulting residue and stirred for 30 min. The resulting solid was filtered, washed with DCM (3 × 5 mL), and dried under vacuum. The resulting crude product (0.135 g) was purified by preparative HPLC to give compound 1.4.

[0450] Table 3, shown below, provides mass spectral data for compounds of the present invention. Compounds for which data is provided below but for which synthetic instructions are not explicitly provided above were made in a manner similar to the synthetic procedures provided in Example 1 above.

[0451] [Table 4]

[0452] Example 2: Preparation of Compound No. 1.6 Step I: {4-[(2S)-5-(carbamoylamino)-2-[(2S)-3-methyl-2-{[(prop-2-en-1-yloxy)carbonyl]amino}butanamido]pentanamido]phenyl}methyl N-[(4-{6-fluoro-9-oxo-3,10-diazatricyclo[6.4.1.0 4 , 13 Preparation of ]trideca-1,4,6,8(13)-tetraen-2-yl}phenyl)methyl]-N-methylcarbamate (Formula 2a)

[0453] [ka]

[0454] DIPEA (0.22 mL, 1.3 mmol) was added to a stirred solution of the compound of Formula 1l (0.4 g, 0.64 mmol) and rucaparib (0.21 g, 0.64 mmol) in DMF (5 mL) at RT, and the mixture was stirred for 2 h. The reaction mixture was concentrated under reduced pressure at 55 °C. The resulting crude material was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol, 90:10) to give compound of Formula 2a.

[0455] Step II: {4-[(2S)-2-[(2S)-2-amino-3-methylbutanamido]-5-(carbamoylamino)pentanamido]phenyl}methyl N-[(4-{6-fluoro-9-oxo-3,10-diazatricyclo[6.4.1.0 4 , 13 Preparation of ]trideca-1,4,6,8(13)-tetraen-2-yl}phenyl)methyl]-N-methylcarbamate (Formula 2b)

[0456] [ka]

[0457] Palladium tetrakis(triphenylphosphine) (0.04 g, 0.035 mmol) was added to a stirred solution of compound of formula 2a (0.38 g, 0.47 mmol) in a mixture of DCM (2.6 mL) and methanol (1.2 mL) at RT. Morpholine (0.3 mL, 3.5 mmol) was added to the reaction mixture, and the mixture was stirred for 4 h. The reaction mixture was then concentrated under reduced pressure at 35 °C. The resulting crude material was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:aqueous ammonia, 83.5:15:1.5) to give compound of formula 2b (0.3 g).

[0458] Step III: Preparation of (Compound No. 1.6).

[0459] [ka]

[0460] Compound 2b (0.1 g, 0.11 mmol) was added to a stirred solution of compound 1i (0.08 g, 0.15 mmol) and triethylamine (0.16 mL, 1.13 mmol) in DMF (2 mL) at RT, and the mixture was stirred for 4 h. Further compound 1i (0.23 g, 0.27 mmol) was added to the reaction mixture, and the resulting mixture was stirred for another 4 h. The reaction mixture was concentrated under reduced pressure at 50 °C and degassed. DCM (5 mL) was added to the residue, and the mixture was stirred at RT for 30 min. The resulting product was filtered, washed with DCM (3 × 5 mL), and dried under vacuum. The resulting crude product (0.15 g) was purified by preparative HPLC to give compound No. 1.6 (0.025 g). Mass (m / z) 1481.02 [M+H] + .

[0461] Example 3: Preparation of Compound No. 1.13 Step I: (11S,12R)-3-({[2-(dimethylamino)ethyl]amino}methyl)-7-fluoro-11-(4-fluorophenyl)-12-(1-methyl-1H-1,2,4-triazol-5-yl)-2,3,10-triazatricyclo[7.3.1.0 5 , 13 ]Preparation of trideca-1,5,7,9(13)-tetraen-4-one (Formula 3a).

[0462] [ka]

[0463] N,N-Dimethylethylenediamine (1.7 mL, 15.8 mmol) was added to a stirred solution of talazoparib (0.5 g, 1.3 mmol) and formaldehyde solution (37% aqueous solution, 0.75 mL, 10.5 mmol) in ethanol (5 mL) at RT, and the mixture was further stirred in a sealed tube. The mixture was then heated in a sealed tube at 80° C. for 5 hours. After 5 hours, the reaction mixture was concentrated and degassed under reduced pressure at 80° C. n-Hexane (10 mL) was added to the residue, and the resulting mixture was stirred at RT for 30 minutes. The resulting product was filtered, washed with n-hexane, and dried to give the compound of formula 3a (0.5 g), which was used in the next step without further purification.

[0464] Step II: {4-[(2S)-5-(carbamoylamino)-2-[(2S)-3-methyl-2-{[(prop-2-en-1-yloxy)carbonyl]amino}butanamido]pentanamido]phenyl}methyl N-[2-(dimethylamino)ethyl]-N-{[(11S,12R)-7-fluoro-11-(4-fluorophenyl)-12-(1-methyl-1H-1,2,4-triazol-5-yl)-4-oxo-2,3,10-triazatricyclo[7.3.1.0 5 , 13 ]trideca-1,5,7,9(13)-tetraen-3-yl]methyl}carbamate (Formula 3b).

[0465] [ka]

[0466] HOBt (35 mg, catalytic amount) followed by DIPEA (0.25 mL, 1.7 mmol) were added to a stirred solution of compound of formula 1l (0.35 g, 0.56 mmol) and compound of formula 3a (0.35 g, 0.73 mmol) in DMF (5 mL) at RT. The mixture was stirred for 30 h and then concentrated under reduced pressure at 55 °C. The resulting crude material was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:aqueous ammonia, 87.4:12:0.6) to give compound of formula 3b (0.27 g).

[0467] Step III: {4-[(2S)-2-[(2S)-2-amino-3-methylbutanamido]-5-(carbamoylamino)pentanamido]phenyl}methyl N-[2-(dimethylamino)ethyl]-N-{[(11S,12R)-7-fluoro-11-(4-fluorophenyl)-12-(1-methyl-1H-1,2,4-triazol-5-yl)-4-oxo-2,3,10-triazatricyclo[7.3.1.0 5 , 13 Preparation of ]trideca-1,5,7,9(13)-tetraen-3-yl]methyl}carbamate (Formula 3c)

[0468] [ka]

[0469] Palladium tetrakis(triphenylphosphine) (0.024 g, 0.021 mmol) was added to a stirred solution of compound of formula 3b (0.27 g, 0.28 mmol) in a mixture of DCM (1.9 mL) and methanol (0.8 mL) at RT. Morpholine (0.18 mL, 2.1 mmol) was added to the reaction mixture, and the mixture was stirred for 4 h. The reaction mixture was then concentrated under reduced pressure at 35 °C. The resulting crude material was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:aqueous ammonia, 84:15:1) to give compound of formula 3c.

[0470] Step IV: (2S)-2-({[(1S)-1-carboxy-5-[(2S)-3-(naphthalen-2-yl)-2-{[(1R,4R)-4-[(4-{[(1S)-1-{[(1S)-4-(carbamoylamino)-1-({4-[({[2-(dimethylamino)ethyl]({[(11S,12R)-7-fluoro-11-(4-fluorophenyl)-12-(1-methyl-1H-1,2,4-triazol-5-yl)-4-oxo-2,3,10-triazatricyclo[7.3.1.0 5 , 13 ]trideca-1,5,7,9(13)-tetraen-3-yl]methyl})carbamoyl}oxy)methyl]phenyl}carbamoyl)butyl]carbamoyl}-2-methylpropyl]carbamoyl}butanamido)methyl]cyclohexyl]formamido}propanamido]pentyl]carbamoyl}amino)pentanedioic acid.

[0471] [ka]

[0472] Compound 3c (0.1 g, 0.11 mmol) was added to a stirred solution of compound 1i (0.19 g, 0.22 mmol) and triethylamine (0.16 mL, 1.13 mmol) in DMF (2 mL) at RT, and the resulting mixture was stirred for 4 h. An additional amount of compound 1i (0.04 g, 0.075 mmol) was added to the reaction mixture, and the mixture was stirred for an additional 4 h. The reaction mixture was then concentrated under reduced pressure at 50 °C and degassed. DCM (5 mL) was added to the residue, and the mixture was stirred at RT for 30 min. The resulting solid was filtered, washed with DCM (3 × 5 mL), and dried under vacuum. The crude product was purified by preparative HPLC to give compound No. 1.13. Mass (m / z) -1637.3 [M+H] + .

[0473] Example 4: Preparation of Compound No. 1.8 Step I: Preparation of di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[4-[[(1-ethoxycarbonylcyclobutanecarbonyl)amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate (Formula 4a).

[0474] [ka]

[0475] EEDQ (0.18 g, 0.73 mmol) was added to a stirred solution of the compound of formula 1f (0.4 g, 0.48 mmol) and 1-ethoxycarbonylcyclobutanecarboxylic acid (0.093 g, 0.53 mmol) in a mixture of DCM (4 mL) and methanol (2 mL). The mixture was stirred at RT overnight and then concentrated under reduced pressure at 40 °C. Diethyl ether (10 mL) was added to the crude product, and the resulting mixture was stirred at RT for 30 min. The resulting solid was filtered, washed with diethyl ether, and dried under reduced pressure to give compound of formula 4a.

[0476] Step II: Preparation of 1-[[4-[[(1S)-2-[[(5S)-6-tert-butoxy-5-[[(1S)-4-tert-butoxy-1-tert-butoxycarbonyl-4-oxo-butyl]carbamoylamino]-6-oxo-hexyl]amino]-1-(2-naphthylmethyl)-2-oxo-ethyl]carbamoyl]cyclohexyl]methylcarbamoyl]cyclobutanecarboxylic acid (Formula 4b)

[0477] [ka]

[0478] A solution of lithium hydroxide (0.058 g, 1.39 mmol) in water (3 mL) was added to a stirred solution of the compound of formula 4a (0.34 g, 0.34 mmol) in ethanol (7 mL) at RT. The reaction mixture was stirred for 3 hours and then concentrated under reduced pressure at 40° C. Water (5 mL) was added to the residue, and the resulting mixture was acidified to pH 4 using saturated citric acid solution. The aqueous layer was extracted with ethyl acetate (3×20 mL). The combined organic layers were dried over anhydrous sodium sulfate and concentrated under reduced pressure at 40° C. to give the compound of formula 4b.

[0479] Step III: Preparation of di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[4-[[[1-(2,5-dioxopyrrolidin-1-yl)oxycarbonylcyclobutanecarbonylamino]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate (Formula 4c).

[0480] [ka]

[0481] NHS (0.053 g, 0.46 mmol) followed by EEDQ (0.088 g, 0.46 mmol) was added to a stirred solution of the compound of formula 4b (0.25 g, 0.26 mmol) in DMF (4 mL). The reaction mixture was stirred at RT overnight. The reaction mixture was then diluted with DCM (30 mL). The organic layer was washed with water (2 × 15 mL) followed by brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 50 °C to give the compound of formula 4c.

[0482] Step IV: Preparation of (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[1-(2,5-dioxopyrrolidin-1-yl)oxycarbonylcyclobutanecarbonyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid (Formula 4d)

[0483] [ka]

[0484] TFA (1.5 mL) was added to a stirred solution of compound of formula 4c (0.3 g, 0.29 mmol) in DCM (3.0 mL) at RT. The reaction mixture was stirred for 6 h and then concentrated and degassed under reduced pressure at 40° C. The residual solid was triturated with diethyl ether (3×5 mL) and decanted. The resulting solid was dried at 40° C. to give compound of formula 4d.

[0485] Step V: Preparation of Compound No. 1.8

[0486] [ka]

[0487] Note: Compounds of formula 4e were prepared in a similar manner to compounds of formula 1n.

[0488] Triethylamine (0.2 mL, 1.46 mmol) was added to a stirred solution of the compound of formula 4e (0.15 g, 0.14 mmol) in DMF (3 mL). The compound of formula 4d (0.31 g, 0.35 mmol) was added to the mixture, and the resulting mixture was stirred at RT overnight. The mixture was then concentrated under reduced pressure at 50° C. The resulting residue was dissolved in DCM (2 mL) to obtain a clear solution. Diethyl ether (6 mL) was added to the solution, and the resulting mixture was stirred at RT for 3 hours. The resulting product was filtered, washed with diethyl ether, and purified by preparative HPLC to obtain compound No. 1.8. Mass (m / z) 1788.78 [M+H] + .

[0489] Example 5: Preparation of Compound No. 1.3 Step I: Preparation of di-tert-butyl (2S)-2-[[(1S)-5-[[(2S)-2-[[(2S)-2-amino-5-tert-butoxy-5-oxo-pentanoyl]amino]-3-(2-naphthyl)propanoyl]amino]-1-tert-butoxycarbonyl-pentyl]carbamoylamino]pentanedioate (Formula 5d).

[0490] [ka]

[0491] EEDQ (0.3 g, 1.5 mmol) was added to a stirred solution of the compound of formula 5b (0.5 g, 1.2 mmol) and 1-hydroxybenzotriazole (0.21 g, 1.5 mmol) in DMF (5 mL), and the mixture was stirred at RT for 2 h. A solution of the compound of formula 5a (0.8 g, 1.2 mmol) in DMF (5 mL) was added to the reaction mixture, and the mixture was stirred overnight. Piperidine (2 mL) was added to the reaction mixture, and the mixture was stirred at RT for 2 h. The reaction mixture was concentrated under reduced pressure at 50 °C. The resulting crude product was purified by column chromatography (silica gel 230-400 mesh; ethyl acetate:methanol, 95:5) to give compound of formula 5d.

[0492] Step II: Preparation of di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[(2S)-5-tert-butoxy-2-[[1-[[(1S)-1-[[4-(hydroxymethyl)phenyl]carbamoyl]-4-ureido-butyl]carbamoyl]cyclobutanecarbonyl]amino]-5-oxo-pentanoyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate (Formula 5f).

[0493] [ka]

[0494] EEDQ (0.28 g, 1.1 mmol) was added to a stirred solution of the compound of formula 5d (0.5 g, 0.57 mmol) and the compound of formula 5e (0.26 g, 0.63 mmol) in a mixture of DCM (5 mL) and methanol (2.5 mL). The reaction mixture was stirred at RT overnight and then concentrated under reduced pressure at 40 °C. Diethyl ether (10 mL) was added to the crude product, and the resulting mixture was stirred at RT for 30 min. The resulting solid was filtered, washed with diethyl ether, and dried under reduced pressure. The crude product was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol, 90:10) to give the compound of formula 5f.

[0495] Step III: 1,5-di-tert-butyl(2S)-2-({[(2S)-1-(tert-butoxy)-6-[(2S)-2-[(2S)-5-(tert-butoxy)-2-[(1-{[(1S)-4-(carbamoylamino)-1-[(4-{[({2-[({[(19S)-10,19-diethyl-7-hydroxy-14,18-dioxo-17-oxa-3,13-diazapentacyclo[11.8.0.0 2 , 11 .0 4 , 9 .0 15 , 20 Preparation of ]henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-19-yl]oxy}carbonyl)(methyl)amino]ethyl}(methyl)carbamoyl)oxy]methyl}phenyl)carbamoyl]butyl]carbamoyl}cyclobutyl)formamido]-5-oxopentanamido]-3-(naphthalen-2-yl)propanamido]-1-oxohexan-2-yl]carbamoyl}amino)pentanedioate (Formula 5g).

[0496] [ka]

[0497] DIPEA (0.1 mL, 0.43 mmol) followed by bis(4-nitrophenyl)carbonate (0.065 g, 0.21 mmol) was added to a stirred solution of the compound of formula 5f (0.18 g, 0.14 mmol) in DMF (2 mL) at RT under a nitrogen atmosphere. The reaction mixture was stirred for 5 h and then concentrated under reduced pressure at 55° C. The residue was triturated with diethyl ether (5 mL), decanted, and the resulting residue was dried under vacuum at 50° C. to provide di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[(2S)-5-tert-butoxy-2-[[1-[[(1S)-1-[[4-[(4-nitrophenoxy)carbonyloxymethyl]phenyl]carbamo-yl]-4-ureido-butyl]carbamoyl]cyclobutanecarbonyl]amino]-5-oxo-pentanoyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate (Formula 5f′), which was used in the next step without purification.

[0498] The compound of formula 5f' and (19S)-10,19-diethyl-7-hydroxy-14,18-dioxo-17-oxa-3,13-diazapentacyclo[11.8.0.0 2 , 11 .0 4 , 9 .0 15 , 20 Henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-19-yl N-methyl-N-[2-(methylamino)ethyl]carbamate hydrochloride (0.12 g, 0.21 mmol) was dissolved in DMF (2 mL). DIPEA (0.1 mL, 0.43 mmol) was added to the reaction mixture, and the resulting mixture was stirred for 2 h. After 2 h, the reaction mixture was concentrated under reduced pressure at 50 °C to give the crude product of compound of formula 5g, which was purified by column chromatography (silica gel 230-400 mesh, DCM:methanol, 93:7).

[0499] Step IV: Preparation of Compound No. 1.3:

[0500] [ka]

[0501] TFA (0.9 mL) was added to a stirred solution of the compound of formula 5g (0.19 g, 0.11 mmol) in hexafluoropropan-2-ol (3.8 mL) at RT. The reaction mixture was stirred for 4 h and then concentrated and degassed under reduced pressure at 40° C. The residual crude product was purified by preparative HPLC to give compound No. 1.3. Mass (m / z): 1567.27.

[0502] Compound No. 1.1 was prepared in the same manner as in Example 5. The mass (m / z) of Compound No. 1.1 was 1514.31 [M+H] + is.

[0503] Example 6: Preparation of Compound No. 1.2 Step I: (19S)-7-{[(tert-butoxy)carbonyl]oxy}-10,19-diethyl-14,18-dioxo-17-oxa-3,13-diazapentacyclo[11.8.0.0 2 , 11 .0 4 , 9 .0 15 , 20 ]Preparation of henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-19-yl 4-nitrophenyl carbonate (Formula 6a).

[0504] [ka]

[0505] DMAP (3.97 g, 32.5 mmol) was dissolved in DCM (250 mL) to prepare a solution of tert-butyl (19S)-10,19-diethyl-19-hydroxy-14,18-dioxo-17-oxa-3,13-diazapentacyclo[11.8.0.0 2 , 11 .0 4 , 9 .0 15 , 20] was added to a stirred solution of henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-7-yl carbonate (5.0 g, 10.1 mmol) and 4-nitrophenyl chloroformate (3.06 g, 15.2 mmol) at RT. The reaction mixture was stirred for 1 h, diluted with DCM (500 mL), washed with 0.1 N aqueous HCl (3 × 50 mL), and dried over anhydrous sodium sulfate. The DCM was removed under reduced pressure at 40 °C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh, ethyl acetate:DCM, 10:90) to give compound of formula 6a.

[0506] Step II: (19S)-19-{[(2-{[(tert-butoxy)carbonyl](methyl)amino}ethyl)(methyl)carbamoyl]oxy}-10,19-diethyl-14,18-dioxo-17-oxa-3,13-diazapentacyclo[11.8.0.0 2 , 11 .0 4 , 9 .0 15 , 20 ]Preparation of Henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-7-yl tert-butyl carbonate (Formula 6b)

[0507] [ka]

[0508] A solution of compound 6a (3.5 g, 5.3 mmol) in DMF (17.5 mL) was added to a stirred solution of tert-butyl N-methyl-N-[2-(methylamino)ethyl]carbamate (1.1 g, 5.85 mmol) and DIPEA (1.4 mL, 0.798 mmol) in acetonitrile (17.5 mL) at RT. The reaction mixture was stirred for 4 h and concentrated under reduced pressure at 35 °C. The resulting concentrated residue was dissolved in ethyl acetate (175 mL), and the ethyl acetate layer was washed with water (1 × 35 mL), followed by brine solution (1 × 35 mL), and dried over anhydrous sodium sulfate. Concentration under reduced pressure gave the crude product, which was purified by column chromatography (silica gel 230-400 mesh, ethyl acetate:DCM, 30:70) to give compound 6b.

[0509] Step III: (19S)-10,19-diethyl-7-hydroxy-14,18-dioxo-17-oxa-3,13-diazapentacyclo[11.8.0.0 2 , 11 .0 4 , 9 .0 15 , 20 ] Preparation of henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-19-yl N-methyl-N-[2-(methylamino)ethyl]carbamate hydrochloride (Formula 6c).

[0510] [ka]

[0511] HCl (4 M) in 1,4-dioxane (1.65 mL) was added to a stirred solution of the compound of formula 6b (0.33 g, 0.47 mmol) in 1,4-dioxane (1.0 mL) at RT. The reaction mixture was stirred for 5 h, then concentrated and degassed under reduced pressure at 35° C. to give the compound of formula 6c (0.25 g), which was used in the next step without purification.

[0512] Step IV: Preparation of benzyl N-[(1S)-1-[[(1S)-1-[[4-(hydroxymethyl)phenyl]carbamoyl]-4-ureidobutyl]carbamoyl]-2-methylpropyl]carbamate (Formula 6e).

[0513] [ka]

[0514] DIPEA (0.5 mL, 2.6 mmol) was added to a stirred solution of the compound of formula 6d (1.0 g, 2.6 mmol) in a mixture of THF (5 mL) and DMF (5 mL). The reaction mixture was cooled to 0-5 °C. Benzyl chloroformate (50% solution in toluene, 0.9 mL, 2.6 mmol) was added dropwise to the reaction mixture, and the resulting mixture was stirred at 0-5 °C for 1 h. The reaction mixture was then concentrated under reduced pressure at 45 °C and thoroughly degassed. DCM (10 mL) was added to the residue, and the resulting solution was stirred at RT for 30 min. The resulting product was filtered, washed with DCM, and dried to give the compound of formula 6e (1.1 g).

[0515] Step V: (19S)-10,19-diethyl-7-hydroxy-14,18-dioxo-17-oxa-3,13-diazapentacyclo[11.8.0.0 2 , 11 .0 4 , 9 .0 15 , 20 ] Preparation of henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-19-yl N-(2-{[({4-[(2S)-2-[(2S)-2-{[(benzyloxy)carbonyl]amino}-3-methylbutanamido]-5-(carbamoylamino)pentanamido]phenyl}methoxy)carbonyl](methyl)amino}ethyl)-N-methylcarbamate (Formula 6f).

[0516] [ka]

[0517] DIPEA (1.2 mL, 7.0 mmol) followed by bis(4-nitrophenyl)carbonate (1.06 g, 3.5 mmol) was added to a stirred solution of compound of formula 6e (1.2 g, 2.3 mmol) in DMF (10 mL) at RT under a nitrogen atmosphere. The resulting mixture was stirred for 5 hours and then concentrated under reduced pressure at 55° C. Diethyl ether (10 mL) was added to the residue, and the resulting mixture was percolated and decanted to give another residue, which was dried under reduced pressure at 50° C. to give compound of formula 6e′, which was used in the next step without purification.

[0518] The compound of formula 6e' and the compound of formula 6c (1.52 g, 2.8 mmol) were dissolved in DMF (10 mL). DIPEA (1.2 mL, 7.0 mmol) was added to the mixture, and the resulting mixture was stirred for 2 hours. The reaction mixture was concentrated under reduced pressure at 50°C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh, DCM:methanol, 90:10) to give the compound of formula 6f.

[0519] Step VI: (19S)-10,19-diethyl-7-hydroxy-14,18-dioxo-17-oxa-3,13-diazapentacyclo[11.8.0.0 2 , 11 .0 4 , 9 .0 15 , 20 ] Preparation of henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-19-yl N-(2-{[({4-[(2S)-2-[(2S)-2-amino-3-methylbutanamido]-5-(carbamoylamino)pentanamido]phenyl}methoxy)carbonyl](methyl)amino}ethyl)-N-methylcarbamate (Formula 6g).

[0520] [ka]

[0521] Palladium on carbon (10%, 50% wet, 0.1 g) was added to a stirred solution of compound of formula 6f (0.5 g, 0.48 mmol) in a mixture of THF (2.5 mL) and methanol (10 mL) at RT. Hydrogen gas was passed through the reaction mixture to purge it at RT, and the reaction mixture was stirred for 2 hours. After 2 hours, the reaction mixture was filtered through a bed of Celite® and washed with a mixture of excess methanol and THF. The combined filtrate was concentrated under reduced pressure at 45° C. to give compound of formula 6g (0.42 gm), which was used in the next step without further purification.

[0522] Step VII: Preparation of Compound No. 1.2

[0523] [ka]

[0524] DIPEA (0.12 mL, 0.69 mmol) was added to a stirred solution of the compound of formula 6g (0.12 g, 0.12 mmol) in DMF (3 mL). The compound of formula 1i (0.12 g, 0.14 mmol) was added to the mixture, and the resulting mixture was stirred at RT for 24 h. After 24 h, the reaction mixture was concentrated and degassed under reduced pressure at 50° C. DCM (5 mL) was added to the residue, and the mixture was stirred at RT for 30 min. The resulting product was filtered, washed with DCM (3×5 mL), and dried under vacuum. The resulting crude product (0.2 g) was purified by preparative HPLC to give compound No. 1.2 (0.06 g). Mass (m / z): 1664.07

[0525] Example 7: Preparation of Compound No. 1.56 Step I: Preparation of (S)-2-allyloxycarbonylaminopentanedioic acid 5-tert-butyl ester.

[0526] [ka]

[0527] Allyl chloroformate (1.1 mL, 10.3 mmol) was added dropwise to a stirred solution of (S)-2-aminopentanedioic acid 5-tert-butyl ester (2.0 gm, 9.8 mmol) in a mixture of THF (40 ml), DMF (5.0 mL), and DIPEA (2.55 mL, 14.7 mmol) at 0° C. The mixture was stirred for 1 hour and then concentrated under reduced pressure at 50° C. Water (20 mL) was added to the resulting residue, and the aqueous layer was extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with brine solution (1×25 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 45° C. to give (S)-2-allyloxycarbonylaminopentanedioic acid 5-tert-butyl ester (2.25 gm), which was used in the next step without purification.

[0528] Step II: Preparation of (S)-4-allyloxycarbonylamino-4-[2-(2-{2-[2-(2-{2-[2-(2-methoxyethoxy)ethoxy]ethoxy}ethoxy)ethoxy]ethoxy}ethoxy)ethylcarbamoyl]butyric acid tert-butyl ester (Formula 7a).

[0529] [ka]

[0530] TBTU (0.704 gm, 2.2 mmol) was added to a stirred solution of (S)-2-allyloxycarbonylaminopentanedioic acid 5-tert-butyl ester (0.485 gm, 1.68 mmol), 2-(2-{2-[2-(2-{2-[2-(2-methoxyethoxy)ethoxy]ethoxy}ethoxy)ethoxy]ethoxy}ethoxy)ethylamine (0.64 gm, 1.68 mmol), and N,N-diisopropylethylamine (0.73 mL, 4.2 mmol) in DMF (4.85 mL) at RT. The reaction mixture was stirred overnight and then quenched with water (10 mL). The aqueous layer was extracted with ethyl acetate (3 x 30 mL). The combined organic layers were washed with brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure at 35° C. to give compound of formula 7a (1.04 gm) which was used in the next step without purification.

[0531] Step III: Preparation of (S)-4-allyloxycarbonylamino-4-[2-(2-{2-[2-(2-{2-[2-(2-methoxyethoxy)ethoxy]ethoxy}ethoxy)ethoxy]ethoxy}ethoxy)ethylcarbamoyl]butyric acid (Formula 7b).

[0532] [ka]

[0533] TFA (4 mL) was added dropwise to a stirred solution of compound of formula 7a (1.0 gm, 1.53 mmol) in DCM (14 mL) at 0°C, and the mixture was stirred for 15 minutes. The reaction mixture was then stirred at RT for 2 hours. The mixture was concentrated under reduced pressure at 50°C to give the crude product (0.9 gm), which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol, 95:5) to give compound of formula 7b.

[0534] Step IV: Preparation of [(S)-1-(3-oxo-1,3-dihydro-isobenzofuran-5-ylcarbamoyl)-4-ureido-butyl]carbamic acid tert-butyl ester.

[0535] [ka]

[0536] EEDQ (6.8 gm, 27.27 mmol) was added to a stirred solution of (S)-2-tert-butoxycarbonylamino-5-ureidopentanoic acid (5.0 gm, 18.18 mmol) and 6-amino-3H-isobenzofuran-1-one (3.0 gm, 20.0 mmol) in a mixture of DCM (60 mL) and methanol (30 mL). The reaction mixture was stirred at RT overnight and then concentrated under reduced pressure at 45° C. Ethyl acetate (5 mL) was added to the residue and the resulting mixture was stirred for 2 hours. The resulting solid was filtered and dried to give [(S)-1-(3-oxo-1,3-dihydro-isobenzofuran-5-ylcarbamoyl)-4-ureido-butyl]carbamic acid tert-butyl ester.

[0537] Step V: Preparation of (S)-2-amino-5-ureido-pentanoic acid (3-oxo-1,3-dihydro-isobenzofuran-5-yl)amide trifluoroacetate.

[0538] [ka]

[0539] TFA (2.8 mL) was added to a stirred solution of [(S)-1-(3-oxo-1,3-dihydro-isobenzofuran-5-ylcarbamoyl)-4-ureidobutyl]carbamic acid tert-butyl ester (0.7 gm, 1.72 mmol) in DCM (7.0 mL) and stirring was continued at RT for 3 hours. Diethyl ether (20 mL) was added to the reaction mixture and the resulting mixture was stirred for 30 minutes. The ether layer was decanted and the product was dried to give (S)-2-amino-5-ureido-pentanoic acid (3-oxo-1,3-dihydro-isobenzofuran-5-yl)-amide trifluoroacetate.

[0540] Step VI: Preparation of {(S)-2-methyl-1-[(S)-1-(3-oxo-1,3-dihydro-isobenzofuran-5-ylcarbamoyl)-4-ureido-butylcarbamoyl]-propyl}-carbamic acid allyl ester (Formula 7c).

[0541] [ka]

[0542] HATU (5.6 gm, 14.7 mmol) was added to a stirred solution of (S)-2-amino-5-ureidopentanoic acid (3-oxo-1,3-dihydro-isobenzofuran-5-yl)amide trifluoroacetate (5.6 gm, 13.7 mmol), (S)-2-allyloxycarbonylamino-3-methylbutyric acid (2.52 gm, 12.5 mmol), and DIPEA (3.36 mL, 18.7 mmol) in DMF (56 mL), and the mixture was stirred at RT overnight. After completion of the reaction, the reaction mixture was quenched with water (50 mL), and the aqueous layer was extracted with ethyl acetate (3 x 100 mL). The combined organic layers were washed with brine solution (1×50 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50° C. to give the crude product (5.8 gm), which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol, 95:05) to give the compound of formula 7c.

[0543] Step VII: Preparation of ((S)-1-{(S)-1-[3-(3-dimethylamino-propylcarbamoyl)-4-hydroxymethyl-phenylcarbamoyl]-4-ureido-butylcarbamoyl}-2-methyl-propyl)-carbamic acid allyl ester (formula 7d).

[0544] [ka]

[0545] N',N'-Dimethylpropane-1,3-diamine (1.5 mL) was added to the compound of formula 7c (0.5 gm, 0.84 mmol) at RT and the mixture was heated with stirring at 85°C for 2 hours. The reaction mixture was then concentrated under reduced pressure at 50°C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:ammonia, 85:13:2) to give the compound of formula 7d.

[0546] Step VIII: Preparation of ((S)-1-{(S)-1-[3-(3-dimethylaminopropylcarbonyl)-4-({[4-(8-fluoro-6-oxo-3,4,5,6-tetrahydro-1H-azepino[5,4,3-cd]indol-2-yl)-benzyl]methylcarbamoyloxy}methyl)phenylcarbamoyl]-4-ureidobutylcarbamoyl}-2-methylpropyl)carbamic acid allyl ester (Formula 7e).

[0547] [ka]

[0548] DIPEA (0.36 mL, 2.0 mmol) was added to a stirred solution of the compound of formula 7d (0.3 g, 0.5 mmol) in DMF (3 mL) at RT. Bis(4-nitrophenyl)carbonate (0.32 g, 1.0 mmol) was added to the reaction mixture, and the resulting mixture was stirred for 2 hours. The reaction mixture was then concentrated under reduced pressure at 55°C. The residue was triturated with diethyl ether (5 mL). The diethyl ether was decanted, and the resulting residue was dried under reduced pressure to obtain the crude product. The crude product was dissolved in DMF (3 mL), and to this was added rucaparib (0.185 gm, 5.7 mmol), HOBt (57 mg), and DIPEA (0.28 mL, 1.5 mmol) at RT. The reaction mixture was stirred for 30 hours and then concentrated under reduced pressure at 55°C. The crude material obtained was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:ammonia, 86:12:2) to give the compound of formula 7e.

[0549] Step IX: Preparation of [4-(8-fluoro-6-oxo-3,4,5,6-tetrahydro-1H-azepino[5,4,3-cd]indol-2-yl)benzyl]methylcarbamic acid 4-[(S)-2-((S)-2-amino-3-methylbutyrylamino)-5-ureidopentanoylamino]-2-(3-dimethylaminopropylcarbamoyl)benzyl ester (Formula 7f).

[0550] [ka]

[0551] Palladium tetrakis(triphenylphosphine) (0.021 g, 0.018 mmol) was added to a stirred solution of compound of formula 7e (0.22 g, 0.23 mmol) in a mixture of DCM (1.54 mL) and methanol (0.66 mL) at RT. Morpholine (0.16 mL, 1.84 mmol) was added to the mixture, and the reaction mixture was stirred for 2.5 h. The reaction mixture was then concentrated under reduced pressure at 35 °C. The crude material obtained was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:ammonia, 88:10:2) to give compound of formula 7f.

[0552] Step X: {4-[(2S)-5-(carbamoylamino)-2-[(2S)-3-methyl-2-[(4S)-4-[(2,5,8,11,14,17,20,23-octaoxapentacosan-25-yl)carbamoyl]-4-{[(prop-2-en-1-yloxy)carbonyl]amino}butanamido]butanamido]pentanamido]-2-{[3-(dimethylamino)propyl]carbamoyl}phenyl}methyl N-[(4-{6-fluoro-9-oxo-3,10-diazatricyclo[6.4.1.04, 13 Preparation of ]trideca-1,4,6,8(13)-tetraen-2-yl}phenyl)methyl]-N-methylcarbamate (Formula 7g).

[0553] [ka]

[0554] TBTU (0.073 gm, 0.22 mmol) was added to a stirred solution of (S)-4-allyloxycarbonylamino-4-[2-(2-{2-[2-(2-{2-[2-(2-methoxyethoxy)ethoxy]ethoxy}ethoxy)ethoxy]ethoxy}ethoxy)ethylcarbamoyl]butyric acid (0.15 gm, 0.175 mmol), compound of formula 7f (0.64 gm, 1.68 mmol), and N,N-diisopropylethylamine (0.73 ml, 0.45 mmol) in DMF (1.5 mL) at RT. The reaction mixture was stirred overnight and then concentrated under reduced pressure at 55°C. The crude material obtained was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:ammonia, 88:10:2) to give compound of formula 7g.

[0555] Step XI: {4-[(2S)-2-[(2S)-2-[(4S)-4-amino-4-[(2,5,8,11,14,17,20,23-octaoxapentacosan-25-yl)carbamoyl]butanamido]-3-methylbutanamido]-5-(carbamoylamino)pentanamido]-2-{[3-(dimethylamino)propyl]carbamoyl}phenyl}methyl N-[(4-{6-fluoro-9-oxo-3,10-diazatricyclo[6.4.1.04, 13 Preparation of ]trideca-1,4,6,8(13)-tetraen-2-yl}phenyl)methyl]-N-methylcarbamate (Formula 7h).

[0556] [ka]

[0557] Palladium tetrakis(triphenylphosphine) (0.007 g, 0.006 mmol) was added to a stirred solution of compound of formula 7g (0.11 g, 0.076 mmol) in a mixture of DCM (0.77 mL) and methanol (0.33 mL) at RT. Morpholine (0.053 mL, 0.608 mmol) was added to the mixture, and the reaction mixture was stirred for 2.0 h. The reaction mixture was then concentrated under reduced pressure at 35 °C. The resulting crude material was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:ammonia, 84:14:2) to give compound of formula 7h.

[0558] Step XII: Preparation of Compound No. 1.56

[0559] [ka]

[0560] Compound of formula 7h (0.09 gm, 0.066 mmol) was added to a stirred solution of compound of formula 1i (0.075 g, 0.086 mmol) in DMF (1.0 mL) and TEA (0.093 mL, 0.66 mmol), and the mixture was stirred at RT for 14 hours. The reaction mixture was then concentrated and degassed under reduced pressure at 50°C. DCM (5 mL) was added to the residue, and the resulting mixture was stirred at RT for 30 minutes. The resulting solid was filtered, washed with DCM (3 x 5 mL), and dried under vacuum. The resulting crude product (0.2 g) was purified by preparative HPLC to give compound No. 1.56.

[0561] Table 4 below lists compounds that were prepared using methods similar to those illustrated in Example 7.

[0562] [Table 5]

[0563] Example 8: Preparation of Compound No. 1.51 Step I: Preparation of O1-benzyl O5-tert-butyl (2S)-2-(benzyloxycarbonylamino)pentanedioate.

[0564] [ka]

[0565] Potassium carbonate (3.6 g, 26.1 mmol) was added to a stirred solution of (2S)-2-(benzyloxycarbonylamino)-5-tert-butoxy-5-oxo-pentanoic acid (4.4 g, 13.0 mmol) in acetonitrile (44 mL) at RT. The reaction mixture was stirred for 15 minutes, and then benzyl bromide (1.7 mL, 14.3 mmol) was added dropwise to the reaction mixture at RT. The reaction mixture was stirred overnight. The reaction mixture was then filtered, washed with ethyl acetate (3 × 20 mL), and concentrated under reduced pressure at 45 °C. Water (40 mL) was added to the residue, and the aqueous layer was extracted with ethyl acetate (3 × 50 mL). The combined organic layers were washed with 1 N HCl solution (1 × 25 mL), followed by brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 45 °C to give the crude product. The crude product was purified by column chromatography (silica gel 230–400 mesh; ethyl acetate: n-hexane, 50:50) to give O1-benzyl O5-tert-butyl (2S)-2-(benzyloxycarbonylamino)pentanedioate.

[0566] Step II: Preparation of (4S)-5-benzyloxy-4-(benzyloxycarbonylamino)-5-oxo-pentanoic acid.

[0567] [ka]

[0568] TFA (11 mL) was added to a stirred solution of O1-benzyl O5-tert-butyl(2S)-2-(benzyloxycarbonylamino)pentanedioate (2.2 gm, 5.15 mmol) in DCM (33.0 mL). The reaction mixture was stirred at RT for 3 h, then concentrated under reduced pressure at 35°C and thoroughly degassed to give the crude product (2.5 gm), which was purified by column chromatography (silica gel 230-400 mesh; ethyl acetate:n-hexane, 50:50) to give (4S)-5-benzyloxy-4-(benzyloxycarbonylamino)-5-oxo-pentanoic acid.

[0569] Step III: Preparation of benzyl (2S)-2-(benzyloxycarbonylamino)-5-[2-[2-[2-[2-[2-[2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoate (Formula 8a).

[0570] [ka]

[0571] TBTU (2.51 gm, 7.8 mmol) was added to a stirred solution of (4S)-5-benzyloxy-4-(benzyloxycarbonylamino)-5-oxo-pentanoic acid (1.94 gm, 5.2 mmol), 2-(2-{2-[2-(2-{2-[2-(2-methoxyethoxy)ethoxy]ethoxy}ethoxy)ethoxy]ethoxy}ethoxy)ethylamine (2.0 gm, 5.2 mmol), and DIPEA (2.3 mL, 13.04 mmol) in DMF (20 mL) at RT. The reaction mixture was stirred overnight and then concentrated under reduced pressure at 55 °C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol (95:5)) to give compound of formula 8a.

[0572] Step IV: Preparation of (2S)-2-amino-5-[2-[2-[2-[2-[2-[2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid (Formula 8b).

[0573] [ka]

[0574] Palladium on carbon (10%, 50% wet, 0.68 g) was added to a stirred solution of compound of formula 8a (3.4 g, 4.61 mmol) in methanol (34 mL) at RT. The reaction mixture was stirred under hydrogen gas pressure at RT for 2 h. After 2 h, the reaction mixture was passed through a Celite® bed and washed with excess methanol. The combined filtrate was concentrated under reduced pressure at 45° C. to give compound of formula 8b, which was used in the next step without further purification.

[0575] Step V: Preparation of (2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[2-[2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid (Formula 8c).

[0576] [ka]

[0577] Allyl chloroformate (0.43 mL, 4.1 mmol) was added dropwise to a stirred solution of compound of formula 8b (1.9 gm, 3.7 mmol) in a mixture of THF (30 mL), water (30 mL), and potassium carbonate (0.84 g, 5.56 mmol) at 0 °C. The reaction mixture was stirred for 10 min, then brought to RT, where it was stirred overnight. The mixture was then concentrated under reduced pressure at 45 °C. Water (20 mL) was added to the residue, and the aqueous layer was acidified to pH 4 using 2 N HCl solution. The resulting mixture was extracted with ethyl acetate (3 × 50 mL). The combined organic layers were washed with brine solution (1 × 25 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 45 °C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:acetic acid, 78:20:2) to give compound of formula 8c.

[0578] Step VI: [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[2-[2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S) Preparation of -1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (Formula 8e).

[0579] [ka]

[0580] Compounds of formula 8d were prepared by a process similar to that described for compounds of formula 1n.

[0581] TBTU (0.046 gm, 0.15 mmol) was added to a stirred solution of compound of formula 8c (0.085 gm, 0.15 mmol), compound of formula 8d (0.14 gm, 0.11 mmol), and DIPEA (0.024 mL, 0.15 mmol) in DMF (2 mL) at RT. The reaction mixture was stirred overnight at RT and then concentrated under reduced pressure at 55 °C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:aqueous ammonia (89:10:1)) to give compound of formula 8e.

[0582] Step VII: [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-amino-5-[2-[2-[2-[2-[2-[2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[( Preparation of 1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (Formula 8f).

[0583] [ka]

[0584] Palladium tetrakis(triphenylphosphine) (0.007 g, 0.09 mmol) was added to a stirred solution of compound of formula 8e (0.16 g, 0.09 mmol) in a mixture of DCM (1.12 mL) and methanol (0.48 mL) at RT. Morpholine (0.057 mL, 0.66 mmol) was added to the mixture, and the reaction mixture was stirred for 2.5 h. The reaction mixture was then concentrated under reduced pressure at 35 °C. The crude material obtained was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:ammonia, 83:15:2) to give compound of formula 8f.

[0585] Step VIII: Preparation of Compound No. 1.51

[0586] [ka]

[0587] The compound of formula 8f (0.05 gm, 0.029 mmol) was added to a stirred solution of the compound of formula 1i (0.037 g, 0.043 mmol) in DMF (1.0 mL) and TEA (0.04 ml, 0.29 mmol). The reaction mixture was stirred at RT for 14 hours, then concentrated and degassed under reduced pressure at 50°C. DCM (3 mL) and diethyl ether (3 mL) were added to the reaction mixture, and the resulting mixture was stirred at RT for 30 minutes. The resulting product was filtered, washed with DCM (3 x 5 mL), and dried under vacuum. The crude product was purified by preparative HPLC to give compound 1.51.

[0588] Table 5 below lists compounds that were prepared using methods similar to those illustrated in Example 8.

[0589] [Table 6]

[0590] Example 9: Preparation of Compound No. 1.16 Step I: Preparation of 2-[[2-(allyloxycarbonylamino)acetyl]amino]acetic acid (Formula 9a).

[0591] [ka]

[0592] Potassium carbonate (7.85 gm, 56.8 mmol) was added to a stirred solution of glycylglycine (5.0 g, 37.8 mmol) in a mixture of THF (100 mL) and water (100 mL) at RT, and the reaction mixture was stirred for 10 minutes. The reaction mixture was cooled to 0-5°C, and allyl chloroformate (4.82 mL, 45.4 mmol) was added dropwise, and the reaction mixture was continued to stir for 15 minutes. The reaction mixture was stirred overnight at RT. After degassing under reduced pressure at 40°C, water (50 mL) was added to the resulting residue, which was washed with diethyl ether (2 × 100 mL) and then acidified to pH 4 using concentrated HCl. The aqueous layer was further saturated with NaCl and then extracted with THF (3 × 100 mL). The combined THF layers were dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50°C to give compound of formula 9a.

[0593] Step II: Preparation of 9H-fluoren-9-ylmethyl N-[2-[4-(hydroxymethyl)anilino]-2-oxo-ethyl]carbamate (Formula 9b).

[0594] [ka]

[0595] EEDQ (24.95 g, 100.9 mmol) was added to a stirred solution of 2-(9H-fluoren-9-ylmethoxycarbonylamino)acetic acid (20.0 g, 67.2 mmol) and p-aminobenzyl alcohol (9.11 g, 74.0 mmol) in a mixture of DCM (200 mL) and methanol (100 mL). The reaction mixture was stirred at RT overnight and then concentrated under reduced pressure at 40 °C. Diethyl ether (200 mL) was added to the crude product, and the resulting mixture was stirred at RT for 30 minutes. The resulting product was filtered, washed with diethyl ether, and dried under reduced pressure to give compound of formula 9b, which was used in the next step without purification.

[0596] Step III: Preparation of 2-amino-N-[4-(hydroxymethyl)phenyl]acetamide (Formula 9c).

[0597] [ka]

[0598] Piperidine (7.4 mL, 74.5 mmol) was added to a stirred solution of the compound of formula 9b (6.0 g, 14.9 mmol) in DMF (30 mL). The reaction mixture was stirred at room temperature for 1 hour and then concentrated under reduced pressure at 50° C. Diethyl ether (60 mL) was added to the residue, and the resulting mixture was stirred at room temperature for 30 minutes. The resulting product was filtered, washed with diethyl ether (2×10 mL), and dried under vacuum to give the compound of formula 9c.

[0599] Step IV: Preparation of 9H-fluoren-9-ylmethyl N-[(1S)-1-benzyl-2-[[2-[4-(hydroxymethyl)anilino]-2-oxo-ethyl]amino]-2-oxo-ethyl]carbamate (Formula 9d).

[0600] [ka]

[0601] EEDQ (2.78 g, 11.2 mmol) was added to a stirred solution of (2S)-2-(9H-fluoren-9-ylmethoxycarbonylamino)-3-phenyl-propanoic acid (2.9 g, 7.49 mmol) and the compound of formula 9c (1.4 g, 7.49 mmol) in a mixture of DCM (29 mL) and methanol (14.5 mL). The reaction mixture was stirred at room temperature overnight and then concentrated under reduced pressure at 40 °C. Diethyl ether (30 mL) was added to the crude product, and the resulting mixture was stirred at room temperature for 30 minutes. The resulting solid was filtered, washed with diethyl ether, and dried under reduced pressure to give the compound of formula 9d, which was used directly in the next step.

[0602] Step V: Preparation of (2S)-2-amino-N-[2-[4-(hydroxymethyl)anilino]-2-oxo-ethyl]-3-phenyl-propanamide (Formula 9e).

[0603] [ka]

[0604] Piperidine (0.87 mL, 8.8 mmol) was added to a stirred solution of compound of formula 9d (1.0 g, 1.76 mmol) in DMF (5 mL). The reaction mixture was stirred at RT for 1 h and then concentrated under reduced pressure at 50 °C. Diethyl ether (10 mL) was added to the residue, and the resulting mixture was stirred at RT for 30 min. The resulting product was filtered, washed with diethyl ether (2 × 10 mL), and dried under vacuum to give compound of formula 9e.

[0605] Step VI: Preparation of allyl N-[2-[[2-[[(1S)-1-benzyl-2-[[2-[4-(hydroxymethyl)anilino]-2-oxo-ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]carbamate (formula 9f).

[0606] [ka]

[0607] EEDQ (1.6 g, 4.6 mmol) was added to a stirred solution of the compound of formula 9a (0.5 g, 2.3 mmol) and the compound of formula 9e (0.75 g, 2.3 mmol) in a mixture of DCM (5 mL) and methanol (2.5 mL). The reaction mixture was stirred at room temperature overnight and then concentrated under reduced pressure at 40 °C. Diethyl ether (10 mL) was added to the crude product, and the resulting mixture was stirred at RT for 30 min. The resulting product was filtered, washed with diethyl ether, and dried under reduced pressure to give the compound of formula 9f, which was used in the next step without purification.

[0608] Step VII: Preparation of [4-[[2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]phenyl]methyl(4-nitrophenyl)carbonate (Formula 9g).

[0609] [ka]

[0610] DIPEA (0.6 mL, 3.4 mmol) was added to a stirred solution of compound of formula 9f (0.6 g, 1.14 mmol) in DMF (6 mL) at RT. Bis(4-nitrophenyl)carbonate (0.7 g, 2.3 mmol) was added to the reaction mixture. The reaction mixture was stirred for 2 hours and then concentrated under reduced pressure at 55° C. The residue was triturated with diethyl ether (10 mL), decanted, and the resulting residue was dried to give compound of formula 9g, which was used in the next step without further purification.

[0611] Step VIII: Preparation of [4-[[2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (Formula 9h).

[0612] [ka]

[0613] HOBt (45 mg) and DIPEA (0.22 mL, 1.28 mmol) were added to a stirred solution of the compound of formula 9g (0.44 g, 0.64 mmol) and monomethyl auristatin E (0.46 g, 0.64 mmol) in DMF (4.4 mL) at room temperature. The reaction mixture was stirred for 48 h and then concentrated under reduced pressure at 55 °C. The resulting crude material was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:aqueous ammonia, 88:10:2) to give compound of formula 9h.

[0614] Step IX: Preparation of [4-[[2-[[(2S)-2-[[2-[(2-aminoacetyl)amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (Formula 9i).

[0615] [ka]

[0616] Palladium tetrakis(triphenylphosphine) (0.034 g, 0.029 mmol) was added to a stirred solution of compound of formula 9h (0.5 g, 0.39 mmol) in a mixture of DCM (3.5 mL) and methanol (1.5 mL) at RT. Morpholine (0.26 mL, 2.9 mmol) was added to the reaction mixture. The reaction mixture was stirred for 4 h and then concentrated under reduced pressure at 40 °C. The resulting crude material was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol:aqueous ammonia, 88:10:2) to give compound of formula 9i.

[0617] Step X: Preparation of Compound No. 1.16

[0618] [ka]

[0619] DIPEA (0.11 mL, 0.82 mmol) was added to a stirred solution of the compound of formula 9i (0.1 g, 0.082 mmol) in DMF (1 mL), and the reaction mixture was stirred to form a clear solution. The compound of formula 1i (0.092 g, 0.11 mmol) was added, and the reaction mixture was stirred at RT for 24 h. The reaction mixture was then concentrated under reduced pressure at 50 °C and degassed. DCM (10 mL) was added to the residue, and the resulting mixture was stirred at RT for 30 min. The resulting solid was filtered, washed with DCM (3 × 5 mL), and dried under vacuum. The resulting crude product was purified by preparative HPLC to give compound 1.16. Mass 1937.0 [M+H] + .

[0620] Table 6, shown below, provides mass spectral data for compounds of the present invention. Compounds for which data is provided below but for which synthetic instructions are not explicitly provided above were made in a manner similar to the synthetic procedure provided in Example 9 above.

[0621] [Table 7]

[0622] Example 10: Preparation of Compound No. 1.9 Step I: Preparation of tert-butyl 2-[2-[2-(2-tert-butoxy-2-oxo-ethoxy)ethoxy]ethoxy]acetate (Formula 10a).

[0623] [ka]

[0624] Sodium hydride (50% suspension in mineral oil, 4.5 g, 94.2 mmol) was added very slowly to a stirred solution of diethylene glycol (5.0 g, 47.1 mmol) in 1,4-dioxane (50 mL) at RT. The reaction mixture was stirred for 30 min and then cooled to 0–5 °C. tert-Butyl bromoacetate (14.0 mL, 94.2 mmol) was added slowly, and the reaction mixture was stirred for 15 min. The reaction mixture was then stirred overnight at RT and then cooled to 0–5 °C. Once at the specified temperature, the reaction mixture was slowly quenched with saturated ammonium chloride solution (50 mL) and extracted with ethyl acetate (3 × 100 mL). The combined organic layers were washed with brine solution (1×50 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure at 45° C. to give the crude product (8.0 gm), which was purified by column chromatography (silica gel 230-400 mesh; ethyl acetate:n-hexane, 30:70) to give the compound of formula 10a.

[0625] Step II: Preparation of 2-[2-[2-(carboxymethyloxy)ethoxy]ethoxy]acetic acid (Formula 10b).

[0626] [ka]

[0627] TFA (5 mL) was added dropwise to a stirred solution of compound of formula 10a (2.5 gm, 7.46 mmol) in DCM (15 mL) at RT. The reaction mixture was stirred for 2 hours and then concentrated under reduced pressure at 40° C. and thoroughly degassed to give compound of formula 10b (2.0 gm), which was used directly in the next step.

[0628] Step III: Preparation of 2-[2-[2-(2-benzyloxy-2-oxo-ethoxy)ethoxy]ethoxy]acetic acid (Formula 10c).

[0629] [ka]

[0630] TEA (3.25 mL, 23.4 mmol) was added to a stirred solution of the compound of formula 10b (2.0 gm, 9.0 mmol) in acetone (14 mL) at RT. The reaction mixture was stirred for 15 minutes and then cooled to 0-5°C. Benzyl bromide (1.12 mL, 9.46 mmol) was added dropwise to the reaction mixture at 0-5°C, and the reaction mixture was stirred for 15 minutes and then stirred at RT overnight. After completion of the reaction, the reaction mixture was filtered and washed with acetone (3 × 20 mL), and the combined filtrate was concentrated under reduced pressure at 45°C. Water (20 mL) was added to the residue. The resulting mixture was acidified to pH 4 with 2N HCl solution and extracted with ethyl acetate (3 × 40 mL). The combined organic layers were washed with brine solution (1 × 25 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 45 °C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; DCM:methanol, 95:5) to give the compound of formula 10c.

[0631] Step IV: Preparation of di-tert-butyl (2S)-2-[[(1S)-5-[[(2S)-2-[[4-[[[2-[2-[2-(2-benzyloxy-2-oxo-ethoxy)ethoxy]ethoxy]acetyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]-1-tert-butoxycarbonyl-pentyl]carbamoylamino]pentanedioate (Formula 10d).

[0632] [ka]

[0633] TBTU (0.07 g, 0.21 mmol) and DIPEA (0.07 mL, 0.4 mmol) were added to a stirred solution of compound of formula 1f (0.13 g, 0.16 mmol) and compound of formula 10c (0.05 g, 0.16 mmol) in DMF (2 mL) at RT. The reaction mixture was stirred overnight and then concentrated under reduced pressure at 50 °C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh, DCM:methanol, 95:5) to give compound of formula 10d.

[0634] Step V: Preparation of 2-[2-[2-[2-[[4-[[(1S)-2-[[(5S)-6-tert-butoxy-5-[[(1S)-4-tert-butoxy-1-tert-butoxycarbonyl-4-oxo-butyl]carbamoylamino]-6-oxo-hexyl]amino]-1-(2-naphthylmethyl)-2-oxo-ethyl]carbamoyl]cyclohexyl]methylamino]-2-oxo-ethoxy]ethoxy]ethoxy]acetic acid Formula 10e.

[0635] [ka]

[0636] Palladium on carbon (10%, 50% wet, 0.03 g) was added to a stirred solution of compound of formula 10d (0.15 g, 0.134 mmol) in methanol (2.5 mL) at RT. Hydrogen gas was passed through the reaction mixture to purge it at RT, and the reaction mixture was then stirred for 1 hour. The reaction mixture was then filtered through a Celite® bed and washed with excess methanol. The combined filtrate was concentrated under reduced pressure at 45° C. to give compound of formula 10e (0.115 gm), which was used in the next step without further purification.

[0637] Step VI: Preparation of di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[4-[[[2-[2-[2-[2-(2,5-dioxopyrrolidin-1-yl)oxy-2-oxo-ethoxy]ethoxy]ethoxy]acetyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate.

[0638] [ka]

[0639] NHS (0.02 g, 0.17 mmol) and EDAC (0.032 g, 0.17 mmol) were added to a stirred solution of compound of formula 10e (0.1 g, 0.097 mmol) in DMF (2 mL) at RT. The resulting mixture was stirred overnight. Additional NHS (0.011 g, 0.097 mmol) and EDAC (0.019 g, 0.097 mmol) were then added to the reaction mixture, and the reaction mixture was stirred at 55 °C for 4 h. The reaction mixture was quenched with water (4 mL) and extracted with DCM (3 × 10 mL). The combined organic layers were washed with brine solution (1 × 5 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 40 °C to give compound of formula 10f (0.1 g), which was used in the next step without purification.

[0640] Step VII: Preparation of 10 g of (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[2-[2-[2-[2-(2,5-dioxopyrrolidin-1-yl)oxy-2-oxo-ethoxy]ethoxy]ethoxy]acetyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid.

[0641] [ka]

[0642] TFA (0.5 mL) was added to a stirred solution of compound of formula 10f (0.1 g, 0.089 mmol) in DCM (2 mL) at 0-5°C. The reaction mixture was stirred at RT for 6 h. After completion of the reaction, the reaction mixture was concentrated and degassed under reduced pressure at 30°C. The crude product was extracted with diethyl ether (2 x 2 ml). The diethyl ether layer was decanted and dried to give compound of formula 10g, which was used directly in the next step.

[0643] Step VI: Preparation of Compound No. 1.9

[0644] [ka]

[0645] TEA (0.06 mL, 0.45 mmol) was added to a stirred solution of the compound of formula 1n (0.05 g, 0.045 mmol) in DMF (1 mL), and the resulting mixture was stirred to form a clear solution. The compound of formula 10g (0.055 g, 0.057 mmol) was added to the reaction mixture, and the resulting mixture was stirred at RT for 24 h. The reaction mixture was then concentrated under reduced pressure at 50 °C and degassed. DCM (5 mL) was added to the residue, and the resulting mixture was stirred at RT for 30 min. The resulting crude product was filtered, washed with DCM (3 × 5 mL), and dried under vacuum. The crude product was purified using preparative HPLC to give compound No. 1.9, mass 1963.52 [M+H]. + obtained.

[0646] Table 7, shown below, provides mass spectral data for compounds of the present invention. Compounds for which data is provided below but for which synthetic instructions are not explicitly provided above were made in a manner similar to the synthetic procedure provided in Example 10 above.

[0647] [Table 8]

[0648] Example 11: Preparation of Compound No. 1.74 Step I: Preparation of tert-butyl 3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoate.

[0649] [ka]

[0650] N,N-Diisopropylethylamine (0.7 mL, 3.86 mmol) was added to a stirred solution of 4-(4-methoxyphenyl)butanoic acid (0.3 g, 1.54 mmol), tert-butyl 3-[2-[2-[2-(2-aminoethoxy)ethoxy]ethoxy]ethoxy]propanoate (0.5 g, 1.54 mmol), and 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate (HATU, 0.7 g, 1.85 mmol) in N,N-dimethylformamide (10 mL) at room temperature and stirred overnight. The reaction mixture was quenched with DM water (1 × 20 mL) and extracted with ethyl acetate (3 × 30 mL). The combined organic layers were washed with 0.5 N HCl solution (1 × 20 mL), followed by saturated sodium bicarbonate solution (1 × 20 mL), DM water (1 × 20 mL), and brine solution (1 × 20 mL). Finally, it was dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50° C. to give tert-butyl 3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoate (0.75 gm), which was used in the next step without purification.

[0651] Step II: Preparation of 3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid.

[0652] [ka]

[0653] Trifluoroacetic acid (2.25 mL) was added to a stirred solution of tert-butyl 3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoate (0.75 gm, 1.51 mmol) in dichloromethane (7.5 mL) at 0-5°C and stirred for 10 minutes. The reaction mixture was then allowed to reach room temperature and stirred for 3 hours. The reaction mixture was concentrated under reduced pressure at 35°C. Diethyl ether (20 ml) was added to the residue and stirred for 30 minutes. The diethyl ether was then decanted off. This process was repeated three times to remove traces of trifluoroacetic acid and then the residue was dried to give 3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid (0.65 gm) which was used in the next step without purification.

[0654] Step III: Preparation of diethyl 3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]pentanedioate.

[0655] [ka]

[0656] N,N-Diisopropylethylamine (0.63 mL, 3.68 mmol) was added to a stirred solution of diethyl 3-aminopentanedioate (0.3 gm, 1.48 mmol), 3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoic acid (0.65 gm, 1.48 mmol), and 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate (HATU, 0.67 gm, 1.77 mmol) in N,N-dimethylformamide (10 mL) at room temperature and stirred overnight. The reaction mixture was quenched with DM water (1 × 20 mL) and extracted with ethyl acetate (3 × 30 mL). The combined organic layers were washed with 0.5 N HCl solution (1 × 20 mL), followed by saturated sodium bicarbonate solution (1 × 20 mL), DM water (1 × 20 mL), and brine solution (1 × 20 mL). Finally, it was dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50 °C to give the crude product (0.8 gm), which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol, 98:2) to give diethyl 3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]pentanedioate (0.63 gm).

[0657] Step III: Preparation of 3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]pentanedioic acid.

[0658] [ka]

[0659] A solution of lithium hydroxide (0.093 g, 2.21 mmol) in DM water (1.9 mL) was added to a stirred solution of diethyl 3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]pentanedioate (0.63 g, 1.0 mmol) in ethanol (4.4 mL) at room temperature and stirred for 2 h. The reaction mixture was concentrated under reduced pressure at 35 °C. DM water (5 mL) was added to the residue and acidified to pH 4 using 0.5 N HCl solution. The aqueous layer was saturated with solid NaCl and then extracted with ethyl acetate (3×20 mL). The combined organic layers were washed with brine solution (1×10 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure at 45° C. to give 3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]pentanedioic acid (0.53 gm), which was used in the next step without purification.

[0660] Step IV: Preparation of N-[2-[2-[2-[2-[3-[(2,6-oxotetrahydrofuran-4-yl)amino]-3-oxo-propoxy]ethoxy]ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide.

[0661] [ka]

[0662] N,N'-Dicyclohexylcarbodiimide (DCC, 0.24 gm, 1.16 mmol) was added to a stirred solution of 3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]pentanedioic acid (0.53 gm, 0.93 mmol) in tetrahydrofuran (10 mL) at room temperature and stirred overnight. The next day, N,N'-Dicyclohexylcarbodiimide (DCC, 0.24 gm, 1.16 mmol) was added again, followed by molecular sieves (4A). 0, 0.5 gm), and tetrahydrofuran (10 mL) were added to the reaction mixture at room temperature and stirred for 8 hours. The reaction mixture was filtered through a Celite bed and washed with tetrahydrofuran (3 × 10 mL). The combined filtrate was concentrated under vacuum at 45 °C to give N-[2-[2-[2-[2-[3-[(2,6-oxotetrahydrofuran-4-yl)amino]-3-oxo-propoxy]ethoxy]ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide, which was used in the next step without purification, considered as 100% yield (0.51 gm). The actual crude product was approximately 0.8 g, which contained DCU as a by-product. It was used directly in the next step without further purification.

[0663] Step V: Preparation of 5-[[4-[[(1S)-2-[[(5S)-6-tert-butoxy-5-[[(1S)-4-tert-butoxy-1-tert-butoxycarbonyl-4-oxo-butyl]carbamoylamino]-6-oxo-hexyl]amino]-1-(2-naphthylmethyl)-2-oxo-ethyl]carbamoyl]cyclohexyl]methylamino]-3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-pentanoic acid.

[0664] [ka]

[0665] N,N-Diisopropylethylamine (0.3 mL, 1.82 mmol) was dissolved in a mixture of N,N-dimethylformamide (6 mL) and acetonitrile (6 mL) to prepare di-tert-butyl(2S)-2-[[(1S)-5-[[(2S)-2-[[4-(aminomethyl)cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]-1-tert-butoxycarbonyl-pentyl]carbamoyl. To a stirred solution of N-[2-[2-[2-[2-[3-[(2,6-dioxotetrahydrofuran-4-yl)amino]-3-oxo-propoxy]ethoxy]ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide (0.5 g, 0.87 mmol, assumed 100% yield) was added under a nitrogen atmosphere and stirred overnight at room temperature. DM water (10 mL) was added to the reaction mixture, which was acidified to pH 4 with aqueous citric acid (20% solution). It was then extracted with ethyl acetate (3 × 30 mL). The combined organic layers were washed with brine solution (1 × 20 mL) and dried over anhydrous sodium sulfate. The organic layer was concentrated under reduced pressure to give the crude product which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol, 85:15) to give 5-[[4-[[(1S)-2-[[(5S)-6-tert-butoxy-5-[[(1S)-4-tert-butoxy-1-tert-butoxycarbonyl-4-oxo-butyl]carbamoylamino]-6-oxo-hexyl]amino]-1-(2-naphthylmethyl)-2-oxo-ethyl]carbamoyl]cyclohexyl]methylamino]-3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-pentanoic acid (0.66 gm).

[0666] Step VI: Preparation of di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[4-[[[3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-5-(2,3,4,5,6-pentafluorophenoxy)pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate.

[0667] [ka]

[0668] Pentafluorophenol (0.1 g, 0.57 mmol) followed by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (0.11 g, 0.57 mmol) was dissolved in 5-[[4-[[(1S)-2-[[(5S)-6-tert-butoxy-5-[[(1S)-4-tert-butoxy-1-tert-butoxycarbonyl-4-oxo-butyl To a stirred solution of [3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-pentanoic acid (0.65 g, 0.47 mmol) was added at room temperature and stirred overnight. The reaction mixture was quenched with DM water (10 mL) and extracted with dichloromethane (3 × 20 mL). The combined organic layers were washed with brine solution (1×20 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure at 40° C. to give di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[4-[[[3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-5-(2,3,4,5,6-pentafluorophenoxy)pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate (0.7 gm) which was used in the next step without purification.

[0669] Step VII: Preparation of (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-5-(2,3,4,5,6-pentafluorophenoxy)pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid.

[0670] [ka]

[0671] Trifluoroacetic acid (3.5 mL) was added to a stirred solution of di-tert-butyl (2S)-2-[[(1S)-1-tert-butoxycarbonyl-5-[[(2S)-2-[[4-[[[3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-5-(2,3,4,5,6-pentafluorophenoxy)pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioate (0.7 g, 0.45 mmol) in dichloromethane (7 mL) at 0-5 °C. The reaction mixture was then stirred at room temperature for 6 h. The reaction mixture was concentrated under reduced pressure at 30 °C and degassed. The crude product was leached with diethyl ether (2 x 20 ml) and the diethyl ether layer was decanted and dried to give (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-5-(2,3,4,5,6-pentafluorophenoxy)pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid (0.6 gm).

[0672] Step VIII: (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[5-[[(1S)-1-[[(1S)-1-[[3-[2-(dimethylamino)ethylcarbamoyl]-4-[[[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl -carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-methyl-carbamoyl]oxymethyl]phenyl]carbamoyl]-4-ureido-butyl]carbamoyl]-2-methyl-propyl]amino]-3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid.

[0673] [ka]

[0674] Triethylamine (0.09 mL, 0.61 mmol) was dissolved in [4-[[(2S)-2-[[(2S)-2-amino-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[2-(dimethylamino)ethylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2 S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.075 g, 0.061 mmol). (2S)-2-[[(1S)-1-Carboxy-5-[[(2S)-2-[[4-[[[3-[3-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoylamino]-5-oxo-5-(2,3,4,5,6-pentafluorophenoxy)pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid (0.1 g, 0.073 mmol) was added to the reaction mixture and stirred at room temperature for 2 hours. Diethyl ether (6 mL) was added to the reaction mixture and stirred at room temperature for 1 hour.The solid thus obtained was filtered under nitrogen atmosphere, washed with diethyl ether and the crude purified by preparative HPLC to give (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[1-[[(1S)-1-[[4-[[[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]- 2-Methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]methyl-carbamoyl]oxymethyl]phenyl]rubamoyl]-4-ureido-butyl]carbamoyl]cyclobutanecarbonyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid was obtained; mass (m / z) 1214.70 [M+2H].

[0675] Compound No. 1.65 was made in a similar manner to the synthetic procedure provided above in Example 11; 1.65: Mass (m / z) 1090.86 [M+2H]

[0676] Example 12: Preparation of Compound No. 1.78 Step I: Preparation of [4-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl(4-nitrophenyl)carbonate.

[0677] [ka]

[0678] N,N-Diisopropylethylamine (0.35 mL, 2.03 mmol) was added to a stirred solution of allyl N-[(1S)-1-[[(1S)-1-[[3-[3-(dimethylamino)propylcarbamoyl]-4-(hydroxymethyl)phenyl]carbamoyl]-4-ureido-butyl]carbamoyl]-2-methyl-propyl]carbamate (0.4 g, 0.68 mmol) in tetrahydrofuran (4 mL) at room temperature. Bis(4-nitrophenyl)carbonate (0.35 g, 1.15 mmol) was added to the reaction mixture and stirred for 5 hours. The reaction mixture was concentrated under reduced pressure at 40°C. Diethyl ether (20 mL) was added to the residue and stirred at room temperature for 45 minutes. The diethyl ether was decanted off. This process was repeated three times and the residue was then dried to give [4-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl(4-nitrophenyl)carbonate (0.75 g), which was used in the next step without further purification.

[0679] Step II: Preparation of [4-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate.

[0680] [ka]

[0681] 1-Hydroxybenzotriazole (40 mg, catalytic amount) followed by N,N-diisopropylethylamine (0.35 mL, 2.03 mmol) was added to a stirred solution of [4-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl(4-nitrophenyl)carbonate (0.5 g, 0.66 mmol) and monomethyl auristatin E (0.48 g, 0.67 mmol) in N,N-dimethylformamide (10 mL) at room temperature and stirred for 48 h. The reaction mixture was concentrated under reduced pressure at 55°C. The crude material thus obtained was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol:aqueous ammonia 83:15:2) to give [4-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)- 1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.5 g).

[0682] Step III: Preparation of [4-[[(2S)-2-[[(2S)-2-amino-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-rubamate.

[0683] [ka]

[0684] Palladium tetrakis(triphenylphosphine) (0.032 g, 0.028 mmol) was dissolved in a mixture of dichloromethane (3.5 mL) and methanol (1.5 mL) in [4-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4- To a stirred solution of [(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.5 g, 0.37 mmol) was added at room temperature. Morpholine (0.23 mL, 2.61 mmol) was added to the reaction mixture and stirred for 1 hour. The reaction mixture was concentrated under reduced pressure at 40 °C. Diethyl ether (20 mL) was added to the residue and stirred at room temperature for 45 minutes. The diethyl ether was decanted off. This process was repeated three times, and then the residue was dried under reduced pressure at 40°C to give the crude material, which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol:aqueous ammonia, 84:14:2) to give [4-[[(2S)-2-[[(2S)-2-amino-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)- 1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.26 g).

[0685] Step XI: [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[ Preparation of [(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate.

[0686] [ka]

[0687] N,N-Diisopropylethylamine (0.1 mL, 0.49 mmol) was dissolved in N,N-dimethylformamide (5 mL) to prepare a solution of (2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid (0.15 gm, 0.26 mmol), [4-[[(2S)-2-[[(2S)-2-amino-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[ To a stirred solution of (2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.25 gm, 0.2 mmol) and O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate (TBTU, 0.09 gm, 0.26 mmol) was added at room temperature and stirred overnight.The reaction mixture was concentrated under reduced pressure at 55 °C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol:aqueous ammonia (84:14:2) to give [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3- (Dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-butylmethylcarbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.26 g) was obtained.

[0688] Step XII: [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-amino-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)- Preparation of 1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate.

[0689]

change

[0690] Palladium tetrakis(triphenylphosphine) (0.012 g, 0.01 mmol) was dissolved in [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl] in a mixture of dichloromethane (5 mL) and methanol (2.5 mL). To a stirred solution of N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.25 g, 0.14 mmol) was added at room temperature. Morpholine (0.09 mL, 0.96 mmol) was added to the reaction mixture and stirred for 1 hour. The reaction mixture was concentrated under reduced pressure at 35 °C. Diethyl ether (15 mL) was added to the residue and stirred at room temperature for 45 minutes. The diethyl ether was decanted off.This process was repeated three times, and then the residue was dried under reduced pressure at 40°C to give a crude material, which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol:ammonia, 84:14:2) to give [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-amino-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2- There was obtained [3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.22 gm).

[0691] Step XIII: (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[5-[[(1S)-1-[[(1S)-1-[[(1S)-1-[[3-[3-(dimethylamino)propylcarbamoyl]-4-[[[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl Preparation of 2-(2-methyl-propyl)carbamoyl)-2-methyl-propyl]methyl-carbamoyl)oxymethyl]phenyl]carbamoyl]-4-ureido-butyl]carbamoyl]-2-methyl-propyl]carbamoyl]-4-[2-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-4-oxo-butyl]amino]-5-oxo-pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid.

[0692] [ka]

[0693] (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-3-(2-naphthyl)-2-[[4-[[[5-oxo-5-(2,3,4,5,6-pentafluorophenoxy)pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid (0.07 gm, 0.075 mmo l) in N,N-dimethylformamide (2.0 mL) to prepare [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-amino-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido -pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.1 g, 0.058 mmol) and triethylamine (0.08 ml, 0.57 mmol) and stirred at room temperature for 4 hours. Diethyl ether (15 mL) was added to the reaction mixture and stirred at room temperature for 1 hour. The diethyl ether was decanted off. This process was repeated three times.The residue was dried under reduced pressure at 40° C. and purified by preparative HPLC to give (2S)-2-[[(1S)-1-carboxy-5-[[(2S)-2-[[4-[[[5-[[(1S)-1-[[(1S)-1-[[(1S)-1-[[3-[3-(dimethylamino)propylcarbamoyl]-4-[[[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl bamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-methyl-carbamoyl]oxymethyl]phenyl]carbamoyl]-4-ureido-butyl]carbamoyl]-2-methyl-propyl]carbamoyl]-4-[2-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-4-oxo-butyl]amino]-5-oxo-pentanoyl]amino]methyl]cyclohexanecarbonyl]amino]-3-(2-naphthyl)propanoyl]amino]pentyl]carbamoylamino]pentanedioic acid (0.07 gm); mass (m / z) 1242.41 [M+2H].

[0694] Compounds Nos. 1.75 and 1.77 were made in a similar manner to the synthetic procedure provided above in Example 12.

[0695] 1.75:Mass (m / z)1235.61[M+2H]2+ 1.77:Mass (m / z)1146.82[M+2H]2+

[0696] Example 13: Preparation of Compound No. 1.75 Step I: Preparation of 2-[[2-(allyloxycarbonylamino)acetyl]amino]acetic acid.

[0697] [ka]

[0698] Potassium carbonate (7.85 gm, 56.8 mmol) was added to a stirred solution of glycylglycine (5.0 g, 37.8 mmol) in a mixture of tetrahydrofuran (100 mL) and DM water (100 mL) at room temperature and stirred for 10 minutes. The reaction mixture was cooled to 0-5°C. Allyl chloroformate (4.82 mL, 45.4 mmol) was added dropwise to the reaction mixture and stirred at 0-5°C for 15 minutes. The reaction mixture was allowed to warm to room temperature and stirred overnight. Tetrahydrofuran was removed under reduced pressure at 40°C. DM water (50 mL) was added to the residue and back-extracted with diethyl ether (2 x 100 mL). The aqueous layer was acidified to pH 4 using concentrated HCl, saturated with solid sodium chloride, and extracted with tetrahydrofuran (3 x 100 mL). The combined organic layers were dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50° C. to give 2-[[2-(allyloxycarbonylamino)acetyl]amino]acetic acid (7.8 g).

[0699] Step II: Preparation of (2,5-dioxopyrrolidin-1-yl)2-[[2-(allyloxycarbonylamino)acetyl]amino]acetate.

[0700] [ka]

[0701] N-Hydroxysuccinimide (1.86 g, 16.2 mmol) followed by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (3.1 g, 16.2 mmol) were added to a stirred solution of 2-[[2-(allyloxycarbonylamino)acetyl]amino]acetic acid (2.0 g, 9.26 mmol) in N,N-dimethylformamide (20 mL) at room temperature and stirred overnight. The reaction mixture was diluted with dichloromethane (100 mL). The combined organic layers were washed with DM water (2 × 25 mL) followed by brine solution (1 × 25 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure at 40 °C to give (2,5-dioxopyrrolidin-1-yl) 2-[[2-(allyloxycarbonylamino)acetyl]amino]acetate (2.7 gm), which was used in the next step without purification.

[0702] Step III: Preparation of (2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoic acid.

[0703] [ka]

[0704] (2,5-Dioxopyrrolidin-1-yl) 2-[[2-(allyloxycarbonylamino)acetyl]amino]acetate (2.75 gm, 8.78 mmol) was dissolved in a mixture of N,N-dimethylformamide (19.2 mL) and tetrahydrofuran (27.5 mL) at room temperature and stirred. The reaction mixture was cooled to 0-5°C. A pre-stirred clear solution of L-phenylalanine (1.45 gm, 8.78 mmol) and triethylamine (1.1 mL, 7.9 mmol) in DM water (19.2 mL) was added dropwise to the reaction mixture at 0-5°C and stirred for 15 minutes. The reaction mixture was then allowed to warm to room temperature and stirred overnight. The reaction mixture was again cooled to 0-5°C and acidified to pH 4 using 2N HCl solution. It was then extracted with ethyl acetate (3 x 50 mL). The combined organic layers were washed with brine solution (1×50 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50° C. to give (2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoic acid (3.55 g), which was used in the next step without purification.

[0705] Step IV: Preparation of (2,5-dioxopyrrolidin-1-yl)(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoate

[0706] [ka]

[0707] N-Hydroxysuccinimide (1.96 g, 17.1 mmol) followed by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (3.26 g, 17.1 mmol) were added to a stirred solution of (2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoic acid (3.55 g, 9.76 mmol) in N,N-dimethylformamide (35 mL) at room temperature and stirred overnight. The reaction mixture was diluted with dichloromethane (150 mL). The combined organic layers were washed with DM water (1×50 mL) followed by brine solution (1×50 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure at 40° C. to give (2,5-dioxopyrrolidin-1-yl)(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoate (4.7 gm), which was used in the next step without purification.

[0708] Step V: Preparation of 2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetic acid.

[0709] [ka]

[0710] (2,5-Dioxopyrrolidin-1-yl)(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoate (4.7 gm, 10.2 mmol) was dissolved in a mixture of N,N-dimethylformamide (33.7 mL) and tetrahydrofuran (47 mL) at room temperature and stirred. The reaction mixture was cooled to 0-5°C. A pre-stirred clear solution of glycine (0.76 gm, 10.2 mmol) and triethylamine (1.42 mL, 10.2 mmol) in DM water (33.7 mL) was added dropwise to the reaction mixture at 0-5°C and stirred for 15 minutes. The reaction mixture was then allowed to warm to room temperature and stirred overnight. The reaction mixture was again cooled to 0-5°C and acidified to pH 4 using 2N HCl solution. It was then extracted with ethyl acetate (3 x 100 mL). The combined organic layers were washed with brine solution (1×50 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50° C. to give 2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetic acid (2.5 g), which was used in the next step without purification.

[0711] Step VI: Preparation of allyl N-[2-[[2-[[(1S)-1-benzyl-2-oxo-2-[[2-oxo-2-[(3-oxo-1H-isobenzofuran-5-yl)amino]ethyl]amino]ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]carbamate.

[0712] [ka]

[0713] N-Ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 1.24 g, 5.03 mmol) was added to a stirred solution of 2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetic acid (1.55 g, 3.7 mmol) and 6-amino-3H-isobenzofuran-1-one (0.5 g, 3.36 mmol) in a mixture of dichloromethane (16 mL) and methanol (8 mL) and stirred at room temperature overnight. The reaction mixture was concentrated under reduced pressure at 40°C. Diethyl ether (25 mL) was added to the crude product and stirred at room temperature for 30 minutes. The solid thus obtained was filtered and washed with diethyl ether. A mixture of ethyl acetate:n-hexane (75:25) was added to the solid residue, stirred at room temperature for 30 minutes, and dried under reduced pressure to give allyl N-[2-[[2-[[(1S)-1-benzyl-2-oxo-2-[[2-oxo-2-[(3-oxo-1H-isobenzofuran-5-yl)amino]ethyl]amino]ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]carbamate, which was used in the next step without purification.

[0714] Step VII: Preparation of allyl N-[2-[[2-[[(1S)-1-benzyl-2-[[2-[3-[3-(dimethylamino)propylcarbamoyl]-4-(hydroxymethyl)anilino]-2-oxo-ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]carbamate.

[0715] [ka]

[0716] N',N'-Dimethylpropane-1,3-diamine (2.1 mL) was added to allyl N-[2-[[2-[[(1S)-1-benzyl-2-oxo-2-[[2-oxo-2-[(3-oxo-1H-isobenzofuran-5-yl)amino]ethyl]amino]ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]carbamate (0.7 gm, 1.81 mmol) at room temperature and then the reaction mixture was heated at 85°C for 2 hours. The reaction mixture was concentrated under reduced pressure at 50°C to give the crude product which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol:ammonia, 83:15:2) to give allyl N-[2-[[2-[[(1S)-1-benzyl-2-[[2-[3-[3-(dimethylamino)propylcarbamoyl]-4-(hydroxymethyl)anilino]-2-oxo-ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]carbamate (0.6 gm).

[0717] Step VIII: Preparation of [4-[[2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl(4-nitrophenyl)carbonate.

[0718] [ka]

[0719] N,N-Diisopropylethylamine (0.48 mL, 2.75 mmol) was added to a stirred solution of allyl N-[2-[[2-[[(1S)-1-benzyl-2-[[2-[3-[3-(dimethylamino)propylcarbamoyl]-4-(hydroxymethyl)anilino]-2-oxo-ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]amino]-2-oxo-ethyl]carbamate (0.6 g, 0.92 mmol) in tetrahydrofuran (6 mL) at room temperature. Bis(4-nitrophenyl)carbonate (0.5 g, 1.61 mmol) was added to the reaction mixture and stirred for 5 hours. The reaction mixture was concentrated under reduced pressure at 40°C. Diethyl ether (20 mL) was added to the residue and stirred at room temperature for 45 minutes. The diethyl ether was decanted off. This process was repeated three times, and the residue was then dried to give [4-[[2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl(4-nitrophenyl)carbonate, which was used in the next step without further purification (0.75 g).

[0720] Step IX: Preparation of [4-[[2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate.

[0721] [ka]

[0722] 1-Hydroxybenzotriazole (60 mg, catalytic amount) followed by N,N-diisopropylethylamine (0.48 mL, 2.75 mmol) was added to a stirred solution of [4-[[2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl(4-nitrophenyl)carbonate (0.75 g, 0.92 mmol) and monomethyl auristatin E (0.6 g, 0.84 mmol) in N,N-dimethylformamide (10 mL) at room temperature and stirred for 48 h. The reaction mixture was concentrated under reduced pressure at 55°C. The crude material thus obtained was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol:aqueous ammonia 84:15:1) to give [4-[[2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[ [(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.6 g).

[0723] Step X: Preparation of [4-[[2-[[(2S)-2-[[2-[(2-aminoacetyl)amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate.

[0724] [ka]

[0725] Palladium tetrakis(triphenylphosphine) (0.037 g, 0.032 mmol) was dissolved in a mixture of dichloromethane (4.2 mL) and methanol (1.8 mL) in [4-[[2-[[(2S)-2-[[2-[[2-(allyloxycarbonylamino)acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S To a stirred solution of (1R,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.6 g, 0.43 mmol) was added at room temperature. Morpholine (0.28 mL, 3.2 mmol) was added to the reaction mixture and stirred for 1.5 hours. The reaction mixture was concentrated under reduced pressure at 40°C. Diethyl ether (20 mL) was added to the residue and stirred at room temperature for 45 minutes. The diethyl ether was decanted off. This process was repeated three times, and then the residue was dried under reduced pressure at 40°C to give the crude material, which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol:aqueous ammonia, 83.5:15:1.5) to give [4-[[2-[[(2S)-2-[[2-[(2-aminoacetyl)amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate was obtained.(035g).

[0726] Step XI: Preparation of N-[2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide.

[0727] [ka]

[0728] N,N-Diisopropylethylamine (1.8 mL, 10.3 mmol) was added to a stirred solution of 4-(4-methoxyphenyl)butanoic acid (0.8 gm, 4.12 mmol), 2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethanamine (1.0 gm, 4.53 mmol) [synthetic reference: Journal of Organic Chemistry, 1991, vol. 56, #13, pp. 4326-4329], and 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate (HATU, 1.88 gm, 4.94 mmol) in N,N-dimethylformamide (10 mL) at room temperature and stirred overnight. The reaction mixture was quenched with DM water (1 × 20 mL) and extracted with ethyl acetate (3 × 30 mL). The combined organic layers were washed with 0.5 N HCl solution (1 × 20 mL), followed by saturated sodium bicarbonate solution (1 × 20 mL), DM water (1 × 20 mL), and brine solution (1 × 20 mL). Finally, it was dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50 °C to give the crude product (2.1 gm), which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol, 97:3) to give N-[2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide (1.3 gm).

[0729] Step XII: Preparation of N-[2-[2-[2-(2-aminoethoxy)ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide.

[0730] [ka]

[0731] Triphenylphosphine (0.96 gm, 4.02 mmol) was added to a stirred solution of N-[2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide (1.32 gm, 3.35 mmol) in tetrahydrofuran (20 mL) at room temperature and stirred overnight. DM water (20 mL) was added to the reaction mixture and heated to reflux at 80° C. for 1 hour. Tetrahydrofuran was removed under reduced pressure at 40° C. DM water (20 mL) was added to the residue, which was then extracted with dichloromethane (3×30 mL). The combined organic layers were washed with brine solution (1×20 mL) and dried over anhydrous sodium sulfate. The organic layer was concentrated under reduced pressure to give the crude product, which was purified by column chromatography (silica gel 230–400 mesh; dichloromethane:methanol:aqueous ammonia, 89:10:1) to give 3 N-[2-[2-[2-(2-aminoethoxy)ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide.

[0732] Step XIII: Preparation of benzyl (2S)-2-(benzyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoate.

[0733] [ka]

[0734] N,N-Diisopropylethylamine (0.84 mL, 4.89 mmol) was added to a stirred solution of N-[2-[2-[2-(2-aminoethoxy)ethoxy]ethoxy]ethyl]-4-(4-methoxyphenyl)butanamide (0.72 gm, 1.95 mmol), (4S)-5-benzyloxy-4-(benzyloxycarbonylamino)-5-oxo-pentanoic acid (0.8 gm, 2.15 mmol), and O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate (TBTU, 0.94 gm, 2.93 mmol) in N,N-dimethylformamide (8 mL) at room temperature and stirred for 5 hours. DM water (20 mL) was added to the residue, which was then extracted with ethyl acetate (3 x 30 mL). The combined organic layers were washed with DM water (1 × 20 mL), followed by brine solution (1 × 20 mL), and dried over anhydrous sodium sulfate. The organic layer was concentrated under reduced pressure to give the crude product (1.6 gm), which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol, 95:5) to give benzyl (2S)-2-(benzyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoate (1.3 g).

[0735] Step XIV: Preparation of (2S)-2-amino-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid

[0736] [ka]

[0737] 10% Palladium on carbon (50% wet) (0.24 g) was added to a stirred solution of benzyl (2S)-2-(benzyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoate (1.2 g, 1.66 mmol) in methanol (10 mL). The reaction mixture was stirred at room temperature for 3 hours under hydrogen pressure applied through a balloon filled with hydrogen gas. The reaction mixture was filtered through a celite bed and washed with methanol (2 x 50 mL). The combined filtrate was concentrated under reduced pressure to give (2S)-2-amino-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid (0.72 gm) which was used in the next step without purification.

[0738] Step XV: Preparation of (2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid.

[0739] [ka]

[0740] Potassium carbonate (0.3 gm, 2.17 mmol) was added to a stirred solution of (2S)-2-amino-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid (0.68 g, 1.41 mmol) in a mixture of tetrahydrofuran (14 mL) and DM water (14 mL). The reaction mixture was cooled to 0-5°C. Allyl chloroformate (0.16 mL, 1.55 mmol) was added dropwise to the reaction mixture and stirred at 0-5°C for 1 hour. Tetrahydrofuran was removed under reduced pressure at 40°C. DM water (10 mL) was added to the residue, cooled to 0-5°C, and acidified to pH 4 using 2N HCl solution. It was saturated with solid sodium chloride and extracted with ethyl acetate (3 x 50 mL). The combined organic layers were washed with brine solution (1×20 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure at 50° C. to give the crude product (0.8 gm), which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol, 90:10) to give (2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid (0.4 g).

[0741] Step XVI: [4-[[(2S)-2-[[(2S)-2-[[(2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[2-[2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]-3-methyl-butanoyl]amino]-5-ureido-pentanoyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[( Preparation of 1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate.

[0742] [ka]

[0743] N,N-Diisopropylethylamine (0.07 mL, 0.38 mmol) was dissolved in N,N-dimethylformamide (2 mL) in (2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoic acid (0.115 gm, 0.198 mmol), [4 -[[2-[[(2S)-2-[[2-[[2-[[(2S)-2-amino-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propanoyl]amino]acetyl]amino] N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo -butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.2 gm, 0.152 mmol) and O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate (TBTU, 0.063 gm, 0.198 mmol) at room temperature and stirred overnight.The reaction mixture was concentrated under reduced pressure at 55 °C to give the crude product, which was purified by column chromatography (silica gel 230-400 mesh; dichloromethane:methanol:aqueous ammonia (87.5:12:0.5) to give [4-[[2-[[(2S)-2-[[2-[[2-[[(2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl yl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate (0.16 g).

[0744] Step XVII: [4-[[2-[[(2S)-2-[[2-[[2-[[(2S)-2-amino-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino)propylcarbamoyl]phenyl]methyl N-[(1S)-1- Preparation of [[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate.

[0745]

change

[0746] Palladium tetrakis(triphenylphosphine) (0.008 g, 0.0064 mmol) was dissolved in a mixture of dichloromethane (1.2 mL) and methanol (0.5 mL) in [4-[[2-[[(2S)-2-[[2-[[2-[[(2S)-2-(allyloxycarbonylamino)-5-[2-[2-[2-[2-[4-(4-methoxyphenyl)butanoylamino]ethoxy]ethoxy]ethoxy]ethylamino]-5-oxo-pentanoyl]amino]acetyl]amino]acetyl]amino]-3-phenyl-propanoyl]amino]acetyl]amino]-2-[3-(dimethylamino) To a stirred solution of N-[(1S)-1-[[(1S)-1-[[(1S,2R)-4-[(2S)-2-[(1R,2R)-3-[[(1R,2S)-2-hydroxy-1-methyl-2-phenyl-ethyl]amino]-1-methoxy-2-methyl-3-oxo-propyl]pyrrolidin-1-yl]-2-methoxy-1-[(1S)-1-methylpropyl]-4-oxo-butyl]-methyl-carbamoyl]-2-methyl-propyl]carbamoyl]-2-methyl-propyl]-N-methyl-carbamate ...

Claims

1. Formula I 【Chemistry 1】 or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein n is 0, 1, 2, 3, or 4; L is a ligand; R １ is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R １ is unsubstituted or is substituted with one or more R ５ is replaced by R ５ is, in each occurrence, independently a halogen, —C(O)NH ２ , -C(O)OR ６ , -C １－３ Alkyl, -OR ７ and 6- to 10-membered aryl; R ６ is hydrogen or C １－３ is alkyl, R ７ is hydrogen or C １－３ is alkyl, R ２ is absent or is selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R ３ is hydrogen or -C １ -C ５ COOH, R ４ But, -C １－１０ Alkyl-, -C ２－６ Alkenyl-, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl-(-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, A is linked to Q via its C-terminus, Q is a self-immolative group; A compound, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein D is a cytotoxic agent or a therapeutic agent.

2. The ligand L is of formula L １ : 【Chemistry 2】 is a ligand of the formula t １ is 0, 1, 2, 3, or 4; t ２ is 1, 2, 3, or 4; Z is N(R ９ ), formula Z １ , and formula Z ２ : 【Transformation 3】 wherein: t ３ is selected from 1, 2, 3, 4, 5, or 6; t ４ is selected from 1, 2, 3, 4, 5, or 6; Y is -CH ２ - or -NH-, 【Chemistry 4】 But, formula L １ represents a bond to the remainder of the compound of formula I, R ９ But hydrogen, C １－５ is selected from the group consisting of alkyl, 6- to 10-membered aryl, and 5- to 10-membered heterocyclyl ring, said heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R ９ 2. The compound of claim 1, wherein is unsubstituted or substituted with a halogen.

3. t １ is 3, Z is N(R ９ ) and R ９ 3. The compound of claim 2, wherein is hydrogen or phenyl, which is unsubstituted or substituted with a halogen.

4. t １ is 1, and Z is the formula Z ２ 3. The compound of claim 2, wherein

5. t1 is 0, and Z is a group represented by the formula Z １ and Y is -NH-.

6. The amino acid in A, at each occurrence, is independently alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group of Formula A1 or Formula A2 【Transformation 5】 and wherein the amino acid is selected from the group consisting of amino acids having the formula: m １ and m １ ' is 0, 1, 2, or 3, m ２ and m ２ ' is 0, 1, 2, 3, or 4, R １０ But (-C ２ H ４ O) １－２４ CH ３ , (-C ２ H ４ O) １－２４ C １－２ Alkyl (N(R １０’ ) (R １０’’ ))-, C １－３ Alkyl-aryl, or -C １－３ Alkyl-Het １ -(-C ２ H ４ O) １－２４ CH ３ Het １ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and said aryl is selected from 6-14 membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R １０’ and R １０’’ are independently hydrogen, C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ The compound of claim 1 , optionally substituted with alkyl.

7. The amino acids in A are, at each occurrence, independently selected from alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), citrulline (cit), homocitrulline (hct), homocysteine ​​(hcy), １ Or Formula A ２ and wherein the amino acid is selected from amino acids having the formula: m １ and m １ ' is 0, 1, or 2, m ２ is 2, m ２ ' is 4, R １０ But (-C ２ H ４ O) ６－８ CH ３ , (-C ２ H ４ O) ３ C ２ H ４ (NH(C(O)C ３ H ６ -aryl))-, C ３ H ６ -aryl, or -CH ２ -Het １ -(-C ２ H ４ O) ８ CH ３ Het １ The compound of claim 6, wherein is triazolyl and aryl is 4-methylphenyl or 4-methoxyphenyl.

8. A is a peptide selected from the group consisting of ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-gly-phe-gly, asp-cit, asp-val-cit, and asp-val, or said peptide has the following formula: 【Transformation 6】 【Transformation 7】 【Transformation 8】 2. The compound of claim 1 selected from the group of compounds having the formula:

9. The self-immolative group Q is of the formula Q １ : 【Chemistry 9】 wherein: R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N(R １９ )-C １－５ Alkyl-N(R １９ )-C(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N[C １－５ Alkyl-N(R ２０ R ２１ ) ]-C １－３ Alkyl- ＊＊ , and -C １－３ Alkyl-O—C(O)-Het ２ -C １－３ Alkyl-N(R １９ )-C(O)- ＊＊ is selected from the group consisting of R １９ is hydrogen, -C １－３ Alkyl, or -C １－３ Alkyl-O-C １－３ alkyl-OH; R ２０ is hydrogen or -C １－３ is alkyl, R ２１ is hydrogen or -C １ - ３ is alkyl, Het ２ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R １２ is hydrogen, —C(O)N(R １３ ) (R １４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R １３ is hydrogen, R １４ But, -C １－５ Alkyl, -C ２－５ Alkenyl, -C ２－５ Alkynyl, —C １－５ Alkyl-N(R １５ ) (R １６ ), -C １－５ Alkyl-O-C １－３ Alkyl, -(-C ２ H ４ O) １－１０ C ２ H ５ , -(-C ２ H ４ O) １－１０ -C ２ H ４ -R １７ , -C １－３ Alkyl-Het ３ -(-C ２ H ４ O) １－１０ -C ２ H ４ -R １８ , or 【Chemistry 10】 is selected from R １５ is hydrogen or C1-C3 alkyl, R １６ is hydrogen or C1-C3 alkyl, or R １５ and R １６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or １－３ substituted with alkyl, halogen, or —OH; R １７ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from R １８ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from Het ３ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R １３ and R １４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ is replaced by R ２２ is hydrogen, —C(O)N(R ２３ ) (R ２４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R ２３ is hydrogen, R ２４ But, -C １－５ Alkyl, -C ２－５ Alkenyl, -C ２－５ Alkynyl, —C １－５ Alkyl-N(R ２５ ) (R ２６ ), -C １－５ Alkyl-O-C １－３ Alkyl, -(-C ２ H ４ O) １－１０ C ２ H ５ , -(-C ２ H ４ O) １－１０ -C ２ H ４ -R ２７ , -C １－３ Alkyl-Het ３ -(-C ２ H ４ O) １－１０ -C ２ H ４ -R ２８ , or 【Chemistry 11】 is selected from R ２５ is hydrogen or C1-C3 alkyl, R ２６ is hydrogen or C1-C3 alkyl, or R ２５ and R ２６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or １－３ substituted with alkyl, halogen, or —OH; R ２７ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from R ２８ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from Het ３ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R ２３ and R ２４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ is replaced by 【Chemistry 12】 indicates the attachment point of Q to the C-terminus of A, ＊＊ 2. The compound of claim 1, wherein indicates the point of attachment of Q to D.

10. R １ is selected from a 6- to 10-membered aryl or a 5- to 10-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; or R １ is unsubstituted or is substituted with one or more R ５ is replaced by R ５ is, in each occurrence, independently selected from halogen, —OH, —OCH ３ , -OC ２ H ５ or 6- to 10-membered aryl; R ２ is selected from the group consisting of 5- to 6-membered cycloalkyl and 6- to 10-membered aryl; R ３ is hydrogen, R ４ But, -C １－１０ Alkyl-, -C ２－６ Alkenyl-, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl-(-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; A is cit, ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala (beta)-v al-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-gly-phe-gly, formula P ３ , formula P ５ , formula P ９ , formula P １２ , formula P １３ , formula P １４ , formula P １５ , and formula P １６ 2. The compound of claim 1 selected from the group consisting of:

11. n is 1, R １ is naphthyl, R ２ is cyclohexyl or phenyl, R ３ is hydrogen, R ４ But, -C １－１０ Alkyl-, -C ２－６ Alkenyl-, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl-(-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; A is cit, ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala (beta)-val-cit , glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-phe-gly, gly-gly-phe-gly, formula P ３ , formula P ５ , formula P ９ , formula P １２ , formula P １３ , formula P １４ , formula P １５ , and formula P １６ 2. The compound of claim 1 selected from the group consisting of:

12. R ４ But, -C ２－５ Alkyl, —CH ２ =CH ２ -, -CH ２ -O-CH ２ -, -CH ２ (-OC ２ H ４ ) ２ -OCH ２ - and cyclobutyl; A is selected from the group consisting of cit, val-ala, val-cit, gly-gly-phe-gly, or the peptide has the formula P ３ , formula P ５ , formula P ９ , formula P １２ , formula P １３ , formula P １４ , formula P １５ , and formula P １６ 12. The compound of claim 11 selected from the group consisting of:

13. R ４ But, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-and-C １－２ Alkyl-(-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; 12. The compound of claim 11, wherein A is selected from the group consisting of val-cit, gly-gly-phe-gly.

14. R ４ But, -C ２－５ selected from the group consisting of alkyl and 3- to 6-membered cycloalkyl; 12. The compound of claim 11, wherein A is selected from the group consisting of cit, val-ala, val-cit, glu-val-cit, and gly-gly-phe-gly.

15. n is 0, 1, or 2; R １ is selected from the group consisting of phenyl, indolyl, thiophenyl, quinolinyl, and isoquinolinyl, or R １ is unsubstituted or has one or more R ５ is replaced by R ５ is selected from halogen, —OH, or a 6- to 10-membered aryl ring; R ２ is cyclohexyl or phenyl, R ３ is hydrogen, R ４ But, -C １－１０ is alkyl, A is val-cit, Q is a compound of the formula Q1 【Chemistry 13】 is a radical of the formula R １１ But -CH ２ OC(O)-, R １２ The compound of claim 1 , wherein is hydrogen.

16. R １ is selected from 6- to 10-membered aryl; R ２ But it doesn't exist, R ３ But -CH ２ COOH, -CH ２ CH ２ COOH, R ４ is a 3- to 6-membered cycloalkyl; A is Cit, Q is a compound of the formula Q1 【Chemistry 14】 is a radical of the formula R １１ But -CH ２ -O-C(O)-N(CH ３ )-C ２ H ４ -N(CH ３ )—C(O)—, R １２ The compound of claim 1 , wherein is hydrogen.

17. n is 0, 1, or 2; R １ is selected from 6- to 10-membered aryl; R ２ is cyclohexyl or phenyl, R ３ is hydrogen, R ４ But, -C １－１０ Alkyl- and -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; A is val-cit, gly-gly-phe-gly, formula P ２ , formula P １３ , formula P １４ , formula P １５ , and formula P １６ is selected from the group consisting of Q is the formula Q １ 【Chemistry 15】 wherein: R １１ But -CH ２ —O—C(O)—, R １２ is hydrogen or —C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, and R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ), or 【Chemistry 16】 is selected from R ２２ is hydrogen or —C(O)N(R ２３ ) (R ２４ ) and R ２３ is hydrogen, and R ２４ But, -C １－５ Alkyl-N(R ２５ ) (R ２６ ), or 【Chemistry 17】 is selected from R １２ and R ２２ 10. The compound of claim 1, wherein at least one of is hydrogen.

18. L is of the formula: [Chemistry 18] is a ligand of R １ but, 【Chemistry 19】 and n is 1, R ２ but, 【Chemistry 20】 and R ３ is hydrogen, R ４ But, -C ３ H ６ - and A is val-cit, 【Chemistry 21】 but, 【Chemistry 22】 and 2. The compound of claim 1, wherein D is monomethyl auristatin E (MMAE).

19. Formula II: 【Chemistry 23】 or a pharmaceutically acceptable salt, solvate, stereoisomer, or isotope thereof, wherein: n is 0, 1, 2, 3, or 4; L is a ligand; R １ is selected from a 6- to 14-membered aryl or a 5- to 13-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R １ is unsubstituted or is substituted with one or more R ５ is replaced by R ５ is, in each occurrence, independently a halogen, —C(O)NH ２ , -C(O)OR ６ , -C １－３ Alkyl, -OR ７ and 6- to 10-membered aryl; R ６ is hydrogen or C １－３ is alkyl, R ７ is hydrogen or C １－３ is alkyl, R ２ is absent or is selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R ３ is hydrogen or -C １ -C ５ COOH, R ４ But, -C １－１０ Alkyl-, -C ２－６ Alkenyl-, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl-(-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, A is linked to Q via its C-terminus, R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N(R １９ )-C １－５ Alkyl-N(R １９ )-C(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N[C １－５ Alkyl-N(R ２０ R ２１ ) ]-C １－３ Alkyl- ＊＊ , or -C １－３ Alkyl-O—C(O)-Het ２ -C １－３ Alkyl-N(R １９ )-C(O)- ＊＊ is selected from ＊＊ indicates the point of attachment to D, R １９ But H, -C １－３ Alkyl, or -C １－３ Alkyl-O-C １－３ alkyl-OH; R ２０ is H or -C １－３ is alkyl, R ２１ is H or -C １ -C ３ is alkyl, Het ２ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R １２ is hydrogen, —C(O)N(R １３ ) (R １４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R １３ is hydrogen, R １４ But, -C １－５ Alkyl, -C ２－５ Alkenyl, -C ２－５ Alkynyl, —C １－５ Alkyl-N(R １５ ) (R １６ ), -C １－５ Alkyl-O-C １－３ Alkyl, -(-C ２ H ４ O) １－１０ C ２ H ５ , -(-C ２ H ４ O) １－１０ -C ２ H ４ -R １７ , or -C １－３ Alkyl-Het ３ -(-C ２ H ４ O) １－１０ -C ２ H ４ -R １８ , or 【Chemistry 24】 is selected from R １５ is hydrogen or C １－３ is alkyl, R １６ is hydrogen or C １－３ alkyl, or R １５ and R １６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or １－３ substituted with alkyl, halogen, or —OH; R １７ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from R １８ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from Het ３ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R １３ and R １４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ is replaced by R ２２ is hydrogen, —C(O)N(R ２３ ) (R ２４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R ２３ is hydrogen, R ２４ But, -C １－５ Alkyl, -C ２－５ Alkenyl, -C ２－５ Alkynyl, —C １－５ Alkyl-N(R ２５ ) (R ２６ ), -C １－５ Alkyl-O-C １－３ Alkyl, -(-C ２ H ４ O) １－１０ C ２ H ５ , -(-C ２ H ４ O) １－１０ -C ２ H ４ -R ２７ , or -C １－３ Alkyl-Het ３ -(-C ２ H ４ O) １－１０ -C ２ H ４ -R ２８ , or 【Chemistry 25】 is selected from R ２５ is hydrogen or C1-C3 alkyl, R ２６ is hydrogen or C1-C3 alkyl, or R ２５ and R ２６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or １－３ substituted with alkyl, halogen, or —OH; R ２７ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from R ２８ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from Het ３ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R ２３ and R ２４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ is replaced by A compound, or a pharmaceutically acceptable salt, solvate, stereoisomer, or isotope thereof, wherein D is a cytotoxic agent or therapeutic agent.

20. The ligand L is of formula L １ : 【Chemistry 26】 is a ligand of the formula t １ is 0, 1, 2, 3, or 4; t ２ is 1, 2, 3, or 4; Z is N(R ９ ), formula Z １ , and formula Z ２ : 【Chemistry 27】 wherein: t ３ is selected from 1, 2, 3, 4, 5, or 6; t ４ is selected from 1, 2, 3, 4, 5, or 6; Y is -CH ２ - or -NH-, 【Chemistry 28】 But, formula L １ represents the bond to the remainder of the compound of formula I, R ９ But hydrogen, C １－５ is selected from the group consisting of alkyl, 6- to 10-membered aryl, and 5- to 10-membered heterocyclyl ring, said heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R ９ 20. The compound of claim 19, wherein is unsubstituted or substituted with a halogen.

21. The amino acid in A, at each occurrence, is independently alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group of formula A １ Or Formula A ２ 【Chemistry 29】 and wherein the amino acid is selected from the group consisting of amino acids having the formula: m １ and m １ ' is 0, 1, 2, or 3, m ２ and m ２ ' is 0, 1, 2, 3, or 4, R １０ But (-C ２ H ４ O) １－２４ CH ３ , (-C ２ H ４ O) １－２４ C １－２ Alkyl (N(R １０’ ) (R １０’’ ))-, C １－３ Alkyl-aryl, or -C １－３ Alkyl-Het １ -(-C ２ H ４ O) １－２４ CH ３ Het １ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and said aryl is selected from 6-14 membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R １０’ and R １０’’ are independently hydrogen, C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ 20. The compound of claim 19, optionally substituted with alkyl.

22. R ２ is a 6- to 10-membered cycloalkyl, and R ３ 20. The compound of claim 19, wherein is hydrogen.

23. R ４ But, -C １－１０ 20. The compound of claim 19, wherein the alkyl is selected from alkyl- or 3- to 6-membered cycloalkyl.

24. R １ 20. The compound of claim 19, wherein is naphthyl.

25. R １２ is -C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ) and R １５ is C1-C3 alkyl, R １６ is C1-C3 alkyl, R ２２ 20. The compound of claim 19, wherein is hydrogen.

26. t １ is 3, Z is N(R ９ ) and R ９ 21. The compound of claim 20, wherein is hydrogen or phenyl.

27. t １ is 1, and Z is the formula Z ２ is a compound of t ３ 21. The compound of claim 20, wherein is 1, 2, 3, 4, 5, or 6.

28. t １ is 0, Z is the formula Z １ is a compound of t ２ is 1, 2, 3, 4, 5, or 6; 21. The compound of claim 20, wherein Y is -NH-.

29. R １ is naphthyl, R ２ is a 6- to 10-membered cycloalkyl; R ３ is hydrogen, R ４ But, -C １－１０ Alkyl- or -C ２－６ Alkyl (N(R ８ ) (R ８’ ))--selected from R ８ and R ８’ are independently hydrogen, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl, R ８ and R ８ ' both, but not hydrogen, R and R' are independently hydrogen or -C(O)-C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl, and both R and R' are not hydrogen; R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ is selected from ＊＊ indicates the point of attachment to D, R １２ is -C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ) and R １５ is C1-C3 alkyl, R １６ is C1-C3 alkyl, R ２２ 20. The compound of claim 19, wherein is hydrogen.

30. A is a peptide selected from the group consisting of ala-ala, ala-ala-ala, ala-phe, val-ala, val-cit, ala-val-cit, ala(beta)-val-cit, glu-val-cit, glu-cit, glu-val, gly-gly, gly-gly-phe, gly-phe-gly, gly-gly-phe-gly, asp-cit, asp-val-cit, and asp-val, or said peptide has the following formula: 【Transformation 30】 【Chemistry 31】 【Chemistry 32】 30. The compound according to any one of claims 19 to 29, selected from the group of compounds having the formula:

31. L is of the formula: 【Transformation 33】 is a ligand of R １ but, 【Transformation 34】 and n is 1, R ２ but, 【Chemistry 35】 and R ３ is hydrogen, R ４ But, -C ３ H ６ - and A is val-cit, 【Transformation 36】 but, 【Chemistry 37】 and 20. The compound of claim 19, wherein D is monomethyl auristatin E (MMAE).

32. Formula III: 【Transformation 38】 or a pharmaceutically acceptable salt, solvate, stereoisomer, or isotope thereof, wherein: L is a ligand; R ４ But, -C １－１０ Alkyl, -C ２－６ Alkenyl, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl (-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N(R １９ )-C １－５ Alkyl-N(R １９ )-C(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N[C １－５ Alkyl-N(R ２０ R ２１ ) ]-C １－３ Alkyl- ＊＊ , or -C １－３ Alkyl-O—C(O)-Het ２ -C １－３ Alkyl-N(R １９ )-C(O)- ＊＊ is selected from ＊＊ indicates the point of attachment to D, R １９ But H, CH ３ , or -C ２ H ４ -O-C ２ H ４ -OH; R ２０ But CH ３ and R ２１ But CH ３ and Het ２ is pyrrolidinyl, R １２ is hydrogen, —C(O)N(R １３ ) (R １４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R １３ is hydrogen, R １４ But -CH ３ , 【Chemistry 39】 -C １－３ Alkyl-N(R １５ ) (R １６ ), -C ２ H ４ OCH ３ , -(-C ２ H ４ O) ３－８ -C ２ H ５ , -(-C ２ H ４ O) ５－１０ -C ２ H ４ -R １７ , -CH ２ -triazole-(-C ２ H ４ O) 4-C ２ H ４ -R １８ , or 【Chemistry 40】 and R １５ But -CH ３ Or -C ２ H ５ and R １６ But -CH ３ Or -C ２ H ５ Or or R １５ and R １６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or is represented by —CH ３ is replaced by R １７ But -C(O)NHC ２ H ４ N (CH ３ ) ２ and R １８ But -C(O)NHC ２ H ４ N (CH ３ ) ２ Or or R １３ and R １４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ is replaced by R ２２ is hydrogen, —C(O)N(R ２３ ) (R ２４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R ２３ is hydrogen, R ２４ But -CH ３ , 【Chemistry 41】 -C １－３ Alkyl-N(R ２５ ) (R ２６ ), -C ２ H ４ OCH ３ , -(-C ２ H ４ O) ３－８ -C ２ H ５ , -(-C ２ H ４ O) ５－１０ -C ２ H ４ -R ２７ , -CH ２ -triazole-(-C ２ H ４ O) ４ -C ２ H ４ -R ２８ , or 【Chemistry 42】 is selected from R ２５ But -CH ３ Or -C ２ H ５ and R ２６ But -CH ３ Or -C ２ H ５ or R ２５ and R ２６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or is represented by —CH ３ is replaced by R ２７ is -C(O)NH-C ２－５ Alkyl-N(CH ３ ) ２ and R ２８ is -C(O)NH-C ２－５ Alkyl-N(CH ３ ) ２ Or or R ２３ and R ２４ together with the nitrogen to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ and D is a cytotoxic or therapeutic agent as defined above, or a pharmaceutically acceptable salt, solvate, stereoisomer, or isotope thereof.

33. The ligand L is of formula L １ : 【Chemistry 43】 wherein: t １ is 0, 1, 2, 3, or 4; t ２ is 1, 2, 3, or 4; Z is N(R ９ ), formula Z １ , and formula Z ２ : 【Chemistry 44】 wherein: t ３ is selected from 1, 2, 3, 4, 5, or 6; t ４ is selected from 1, 2, 3, 4, 5, or 6; Y is -CH ２ - or -NH-, 【Chemistry 45】 But, formula L １ represents the bond to the remainder of the compound of formula I, R ９ But hydrogen, C １－５ is selected from the group consisting of alkyl, 6- to 10-membered aryl, and 5- to 10-membered heterocyclyl ring, said heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R ９ 33. The compound of claim 32, wherein is unsubstituted or substituted with a halogen.

34. The amino acid in A, at each occurrence, is independently alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group of formula A １ Or Formula A ２ 【Chemistry 46】 and wherein the amino acid is selected from the group consisting of amino acids having the formula: m １ and m １ ' is 0, 1, 2, or 3, m ２ and m ２ ' is 0, 1, 2, 3, or 4, R １０ But (-C ２ H ４ O) １－２４ CH ３ , (-C ２ H ４ O) １－２４ C １－２ Alkyl (N(R １０’ ) (R １０’’ ))-, C １－３ Alkyl-aryl, or -C １－３ Alkyl-Het １ -(-C ２ H ４ O) １－２４ CH ３ Het １ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and said aryl is selected from 6-14 membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R １０’ and R １０’’ are independently hydrogen, C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ 33. The compound of claim 32, optionally substituted with alkyl.

35. R ４ But, -C １－１０ Alkyl, -C ２－６ Alkenyl, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl (-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ 33. The compound of claim 32, optionally substituted with alkyl.

36. R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ and ＊＊ indicates the point of attachment to D, R １２ is -C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ) and R １５ But C １－３ is alkyl, R １６ But C １－３ is alkyl, R ２２ 33. The compound of claim 32, wherein is hydrogen.

37. R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ and ＊＊ indicates the point of attachment to D, R １２ is -C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ) and R １５ But C １－３ is alkyl, R １６ But C １－３ is alkyl, R ２２ is -C(O)N(R ２３ ) (R ２４ ) and R ２３ is hydrogen, R ２４ But, -C １－５ Alkyl-N(R ２５ ) (R ２６ ) and R ２５ But C １－３ is alkyl, R ２６ But C １－３ 33. The compound of claim 32, which is alkyl.

38. A is cit, val-ala, val-cit, gly-gly-phe-gly, formula P ３ , formula P ５ , formula P ９ , formula P １２ , formula P １３ , formula P １４ , formula P １５ , and formula P １６ The compound according to any one of claims 32 to 37, selected from:

39. R ４ But, -C ３ H ６ - and A is val-cit, 【Chemistry 47】 but, 【Chemistry 48】 and 33. The compound of claim 32, wherein D is monomethyl auristatin E (MMAE).

40. Formula IV 【Chemistry 49】 or a pharmaceutically acceptable salt, solvate, stereoisomer, or isotope thereof, wherein: L is a ligand and D is a cytotoxic or therapeutic agent as defined above; R ４ But, -C １－１０ Alkyl, -C ２－６ Alkenyl, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl (-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N(R １９ )-C １－５ Alkyl-N(R １９ )-C(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N[C １－５ Alkyl-N(R ２０ R ２１ ) ]-C １－３ Alkyl- ＊＊ , or -C １－３ Alkyl-O—C(O)-Het ２ -C １－３ Alkyl-N(R １９ )-C(O)- ＊＊ is selected from ＊＊ indicates the point of attachment to D, R １９ is H, -CH ３ , or -C ２ H ４ -O-C ２ H ４ -OH; R ２０ But -CH ３ and R ２１ But -CH ３ and Het ２ is pyrrolidine, R １４ But, -C １ -C ５ Alkyl, -C １ -C ５ Alkyl-N(R １５ ) (R １６ ), -C １ -C ５ Alkyl-OCH ３ , (-C ２ H ４ O) １－１０ CH ２ -CH ３ , or [Transformation 50] is selected from R １５ But C １－３ is alkyl, R １６ But C １－３ The compound, or a pharmaceutically acceptable salt, solvate, stereoisomer, or isotope thereof, wherein:

41. The ligand L is of formula L １ : 【Chemistry 51】 wherein: t １ is 0, 1, 2, 3, or 4; t ２ is 1, 2, 3, or 4; Z is N(R ９ ), formula Z １ , and formula Z ２ : 【Chemistry 52】 wherein: t ３ is selected from 1, 2, 3, 4, 5, or 6; t ４ is selected from 1, 2, 3, 4, 5, or 6; Y is -CH ２ - or -NH-, 【Chemistry 53】 But, formula L １ represents the bond to the remainder of the compound of formula I, R ９ But hydrogen, C １－５ is selected from the group consisting of alkyl, 6- to 10-membered aryl, and 5- to 10-membered heterocyclyl ring, said heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R ９ 41. The compound of claim 40, wherein is unsubstituted or substituted with halogen.

42. The amino acid in A, at each occurrence, is independently alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group of formula A １ Or Formula A ２ 【Chemistry 54】 and wherein the amino acid is selected from the group consisting of amino acids having the formula: m １ and m １ ' is 0, 1, 2, or 3, m ２ and m ２ ' is 0, 1, 2, 3, or 4, R １０ But (-C ２ H ４ O) １－２４ CH ３ , (-C ２ H ４ O) １－２４ C １－２ Alkyl (N(R １０’ ) (R １０’’ ))-, C １－３ Alkyl-aryl, or -C １－３ Alkyl-Het １ -(-C ２ H ４ O) １－２４ CH ３ Het １ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and said aryl is selected from 6-14 membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R １０’ and R １０’’ are independently hydrogen, C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ 41. The compound of claim 40, optionally substituted with alkyl.

43. R ４ But, -C ２－５ Alkyl, -C ２－５ Alkyl (N(R ８ ) (R ８’ ))- and 3- to 6-membered cycloalkyl; R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ 41. The compound of claim 40, optionally substituted with alkyl.

44. R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ and ＊＊ indicates the point of attachment to D, R １２ is -C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ), and 【Transformation 55】 is selected from R １５ But C １－３ is alkyl, R １６ But C １－３ 41. The compound of claim 40, which is alkyl.

45. A is cit, val-ala, val-cit, glu-val-cit, gly-gly-phe-gly, formula P ３ , formula P ５ , formula P ９ , formula P １２ , formula P １３ , formula P １４ , formula P １５ , and formula P １６ 41. The compound of claim 40, which is a peptide selected from the group consisting of:

46. R ４ But, -C ３ H ６ - and A is val-cit, 【Transformation 56】 but, 【Chemistry 57】 and 41. The compound of claim 40, wherein D is monomethyl auristatin E (MMAE).

47. Formula V 【Chemistry 58】 or a pharmaceutically acceptable salt, solvate, stereoisomer, or isotope thereof, wherein: L is a ligand; A is an amino acid or a peptide containing 2 to 5 amino acids, R ４ But, -C １－１０ Alkyl, -C ２－６ Alkenyl, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl (-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ is hydrogen or C １－６ is alkyl, R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N(R １９ )-C １－５ Alkyl-N(R １９ )-C(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N[C １－５ Alkyl-N(R ２０ R ２１ ) ]-C １－３ Alkyl- ＊＊ , or -C １－３ Alkyl-O—C(O)-Het ２ -C １－３ Alkyl-N(R １９ )-C(O)- ＊＊ is selected from ＊＊ indicates the point of attachment to D, R １９ is H, -CH ３ , or -C ２ H ４ -O-C ２ H ４ -OH; R ２０ But -CH ３ and R ２１ But -CH ３ and Het ２ is pyrrolidinyl, R １４ But, -C １ -C ５ Alkyl, -C １ -C ５ Alkyl-N(R １５ ) (R １６ ), -C １ -C ５ Alkyl-OCH ３ , (-C ２ H ４ O) １－１０ CH ２ -CH ３ is selected from R １５ But C １－３ is alkyl, R １６ But C １－３ is alkyl, R ２４ But, -C １－５ Alkyl, -C １－５ Alkyl-N(R ２５ ) (R ２６ ), -C １－５ Alkyl-OCH ３ , (-C ２ H ４ O) １－１０ CH ２ -CH ３ is selected from R ２５ is hydrogen or C １－３ is alkyl, R ２６ is hydrogen or C １－３ is alkyl, A compound, or a pharmaceutically acceptable salt, solvate, stereoisomer, or isotope thereof, wherein D is a cytotoxic agent or therapeutic agent.

48. The ligand L is of formula L １ : 【Chemistry 59】 wherein: t １ is 0, 1, 2, 3, or 4; t ２ is 1, 2, 3, or 4; Z is N(R ９ ), formula Z １ , and formula Z ２ : 【Transformation 60】 wherein: t ３ is selected from 1, 2, 3, 4, 5, or 6; t ４ is selected from 1, 2, 3, 4, 5, or 6; Y is -CH ２ - or -NH-, 【Chemistry 61】 But, formula L １ represents the bond to the remainder of the compound of formula I, R ９ But hydrogen, C １－５ is selected from the group consisting of alkyl, 6- to 10-membered aryl, and 5- to 10-membered heterocyclyl ring, said heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R ９ 48. The compound of claim 47, wherein is unsubstituted or substituted with halogen.

49. The amino acid in A, at each occurrence, is independently alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group of formula A １ Or Formula A ２ 【Transformation 62】 and wherein the amino acid is selected from the group consisting of amino acids having the formula: m １ and m １ ' is 0, 1, 2, or 3, m ２ and m ２ ' is 0, 1, 2, 3, or 4, R １０ But (-C ２ H ４ O) １－２４ CH ３ , (-C ２ H ４ O) １－２４ C １－２ Alkyl (N(R １０’ ) (R １０’’ ))-, C １－３ Alkyl-aryl, or -C １－３ Alkyl-Het １ -(-C ２ H ４ O) １－２４ CH ３ Het １ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and said aryl is selected from 6-14 membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R １０’ and R １０’’ are independently hydrogen, C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ 48. The compound of claim 47, optionally substituted with alkyl.

50. R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ and ＊＊ indicates the point of attachment to D, R １２ is -C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ) and R １５ But C １－３ is alkyl, R １６ But C １－３ is alkyl, R ２２ is -C(O)N(R ２３ ) R ２４ and R ２３ is hydrogen, R ２４ But, -C １－５ Alkyl-N(R ２５ ) (R ２６ ) and R ２５ But C １－３ is alkyl, R ２６ But C １－３ 48. The compound of claim 47, which is alkyl.

51. A is cit, val-ala, val-cit, glu-val-cit, gly-gly-phe-gly, formula P ３ , formula P ５ , formula P ９ , formula P １２ , formula P １３ , formula P １４ , formula P １５ , and formula P １６ 48. The compound of claim 47, selected from:

52. Formula VI 【Transformation 63】 or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein: L is a ligand; A is an amino acid or a peptide containing 2 to 5 amino acids, R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N(R １９ )-C １－５ Alkyl-N(R １９ )-C(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N[C １－５ Alkyl-N(R ２０ R ２１ ) ]-C １－３ Alkyl- ＊＊ , or -C １－３ Alkyl-O—C(O)-Het ２ -C １－３ Alkyl-N(R １９ )-C(O)- ＊＊ is selected from ＊＊ indicates the point of attachment to D, R １９ But H, CH ３ , or -C ２ H ４ -O-C ２ H ４ -OH; R ２０ But CH ３ and R ２１ But CH ３ and Het ２ is pyrrolidinyl, R １２ is hydrogen, —C(O)N(R １３ ) (R １４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R １３ is hydrogen, R １４ But -CH ３ , 【Chemistry 64】 -C １－３ Alkyl-N(R １５ ) (R １６ ), -C ２ H ４ OCH ３ , -(-C ２ H ４ O) ３－８ -C ２ H ５ , -(-C ２ H ４ O) ５－１０ -C ２ H ４ -R １７ , -CH ２ -triazole-(-C ２ H ４ O) 4-C ２ H ４ -R １８ , or 【Transformation 65】 and R １５ But -CH ３ Or -C ２ H ５ and R １６ But -CH ３ Or -C ２ H ５ or R １５ and R １６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or is represented by —CH ３ is replaced by R １７ But -C(O)NHC ２ H ４ N (CH ３ ) ２ and R １８ But -C(O)NHC ２ H ４ N (CH ３ ) ２ Or or R １３ and R １４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ is replaced by R ２２ is hydrogen, —C(O)N(R ２３ ) (R ２４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R ２３ is hydrogen, R ２４ But -CH ３ , 【Chemical Formula 66】 -C １－３ Alkyl-N(R ２５ ) (R ２６ ), -C ２ H ４ OCH ３ , -(-C ２ H ４ O) ３－８ -C ２ H ５ , -(-C ２ H ４ O) ５－１０ -C ２ H ４ -R ２７ , -CH ２ -triazolyl-(-C ２ H ４ O) 4-C ２ H ４ -R ２８ , or 【Transformation 67】 and R ２５ But -CH ３ Or -C ２ H ５ and R ２６ But -CH ３ Or -C ２ H ５ or R ２５ and R ２６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with an additional heteroatom independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or is represented by —CH ３ is replaced by R ２７ But -C(O)NHC ２ H ４ N (CH ３ ) ２ and R ２８ But -C(O)NHC ２ H ４ N (CH ３ ) ２ Or or R ２３ and R ２４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ is replaced by A compound, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein D is a cytotoxic agent or a therapeutic agent.

53. The ligand L is of formula L １ : 【Transformation 68】 wherein: t １ is 0, 1, 2, 3, or 4; t ２ is 1, 2, 3, or 4; Z is N(R ９ ), formula Z １ , and formula Z ２ : 【Transformation 69】 wherein: t ３ is selected from 1, 2, 3, 4, 5, or 6; t ４ is selected from 1, 2, 3, 4, 5, or 6; Y is -CH ２ - or -NH-, 【Transformation 70】 But, formula L １ represents the bond to the remainder of the compound of formula I, R ９ But hydrogen, C １－５ is selected from the group consisting of alkyl, 6- to 10-membered aryl, and 5- to 10-membered heterocyclyl ring, said heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R ９ 53. The compound of claim 52, wherein is unsubstituted or substituted with halogen.

54. The amino acid in A, at each occurrence, is independently alanine (ala), arginine (arg), aspartic acid (asp), cysteine ​​(cys), glutamic acid (glu), glycine (gly), lysine (lys), phenylalanine (phe), serine (ser), threonine (thr), tryptophan (trp), valine (val), ornithine (orn), citrulline (cit), homocitrulline (hct), lanthionine (lan), homocysteine ​​(hcy), or a group of formula A １ Or Formula A ２ 【Chemistry 71】 and wherein the amino acid is selected from the group consisting of amino acids having the formula: m １ and m １ ' is 0, 1, 2, or 3, m ２ and m ２ ' is 0, 1, 2, 3, or 4, R １０ But (-C ２ H ４ O) １－２４ CH ３ , (-C ２ H ４ O) １－２４ C １－２ Alkyl (N(R １０’ ) (R １０’’ ))-, C １－３ Alkyl-aryl, or -C １－３ Alkyl-Het １ -(-C ２ H ４ O) １－２４ CH ３ Het １ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and said aryl is selected from 6-14 membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R １０’ and R １０’’ are independently hydrogen, C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ 53. The compound of claim 52, optionally substituted with alkyl.

55. R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ and ＊＊ indicates the point of attachment to D, R １２ is -C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ) and R １５ But C １－３ is alkyl, R １６ But C １－３ is alkyl, R ２２ 53. The compound of claim 52, wherein is hydrogen.

56. R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ and ＊＊ indicates the point of attachment to D, R １２ is -C(O)N(R １３ ) (R １４ ) and R １３ is hydrogen, R １４ But, -C １－５ Alkyl-N(R １５ ) (R １６ ) and R １５ But C １－３ is alkyl, R １６ But C １－３ is alkyl, R ２２ is -C(O)N(R ２３ ) (R ２４ ) and R ２３ is hydrogen, R ２４ But, -C １－５ Alkyl-N(R ２５ ) (R ２６ ) and R ２５ But C １－３ is alkyl, R ２６ But C １－３ 53. The compound of claim 52, which is alkyl.

57. R ４ But, -C ３ H ６ - and A is val-cit, 【Chemistry 72】 but, 【Transformation 73】 and 57. The compound of claim 56, wherein D is monomethyl auristatin E (MMAE).

58. Formula VII 【Chemistry 74】 or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, During the ceremony, L is a ligand; n is 0, 1, or 2; R １ is selected from the group consisting of phenyl, indolyl, thiophenyl, quinolinyl, and isoquinolinyl; R １ is unsubstituted or is substituted with one or more R ５ is replaced by R ５ is selected from halogen, —OH, or a 6- to 10-membered aryl ring; R ２ is cyclohexyl or phenyl, A is the peptide val-cit, A compound, or a pharmaceutically acceptable salt, stereoisomer, or isotope thereof, wherein D is a cytotoxic agent or a therapeutic agent.

59. A method for treating cancer, comprising administering any of the compounds of Formulas I-VII or a medicament comprising same.

60. A method for treating cancer that is positive for PSMA expression, comprising administering a compound according to any one of claims 1 to 59, or a medicament containing said compound.

61. Use of a compound of formula I-VII as defined in any one of claims 1 to 60 for the preparation of a medicament for use in the treatment of cancer.

62. 62. A pharmaceutical composition comprising a compound according to any one of claims 1 to 61 and a pharmaceutically acceptable carrier.

63. A ligand-drug conjugate, wherein the ligand L and the drug D are represented by Formula VIII: 【Chemistry 75】 is conjugated via a linker of the formula: n is 0, 1, 2, 3, or 4; R １ is selected from a 6- to 14-membered aryl or a 5- to 10-membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R １ is unsubstituted or is substituted with one or more R ５ is replaced by R ５ is, in each occurrence, independently a halogen, —C(O)NH ２ , -C(O)OR ６ , -C １－３ Alkyl, -OR ７ and 6- to 10-membered aryl; R ６ is hydrogen or C １－３ is alkyl, R ７ is hydrogen or C １－３ is alkyl, R ２ is absent or is selected from 6- to 10-membered cycloalkyl or 6- to 10-membered aryl; R ３ is hydrogen or -C １ -C ５ COOH, R ４ But, -C １－１０ Alkyl-, -C ２－６ Alkenyl-, -C １－３ Alkyl-O-C １－３ Alkyl-, -C ２－６ Alkyl-N(R ８ ) -, -C ２－６ Alkyl (N(R ８ ) (R ８’ ))-, -N(R ８ )-C ２－６ alkyl-, 3- to 6-membered cycloalkyl, and —C １－２ Alkyl-(-OC ２ H ４ ) １－８ -OC １－２ alkyl-, R ８ and R ８’ are independently hydrogen, C １－６ Alkyl, —C(O)—C １－４ Alkyl-aryl, or —C(O)—(—C ２ H ４ O) １－８ -C １－２ alkyl-N(R)(R'), wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; R and R' are independently hydrogen, -C １－６ Alkyl, or —C(O)—C １－４ alkyl-aryl, wherein said aryl is selected from 6- to 14-membered aryl; １－３ Alkyl or -OC １－３ optionally substituted with alkyl; A is an amino acid or a peptide containing 2 to 5 amino acids, A is bound to NH via its C-terminus, R １１ But, -C １－３ Alkyl-OC(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N(R １９ )-C １－５ Alkyl-N(R １９ )-C(O)- ＊＊ , -C １－３ Alkyl-O—C(O)—N[C １－５ Alkyl-N(R ２０ R ２１ ) ]-C １－３ Alkyl- ＊＊ , and -C １－３ Alkyl-O—C(O)-Het ２ -C １－３ Alkyl-N(R １９ )-C(O)- ＊＊ is selected from the group consisting of R １９ is hydrogen, -C １－３ Alkyl, or -C １－３ Alkyl-O-C １－３ alkyl-OH; R ２０ is hydrogen or -C １－３ is alkyl, R ２１ is hydrogen or -C １ - ３ is alkyl, Het ２ is a 5-10 membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; R １２ is hydrogen, —C(O)N(R １３ ) (R １４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R １３ is hydrogen, R １４ But, -C １－５ Alkyl, -C ２－５ Alkenyl, -C ２－５ Alkynyl, —C １－５ Alkyl-N(R １５ ) (R １６ ), -C １－５ Alkyl-O-C １－３ Alkyl, -(-C ２ H ４ O) １－１０ C ２ H ５ , -(-C ２ H ４ O) １－１０ -C ２ H ４ -R １７ , or -C １－３ Alkyl-Het ３ -(-C ２ H ４ O) １－１０ -C ２ H ４ -R １８ , or 【Transformation 76】 is selected from R １５ is hydrogen or C1-C3 alkyl, R １６ is hydrogen or C1-C3 alkyl, or R １５ and R １６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or １－３ substituted with alkyl, halogen, or —OH; R １７ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from R １８ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from Het ３ is a 5- to 10-membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R １３ and R １４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ is replaced by R ２２ is hydrogen, —C(O)N(R ２３ ) (R ２４ ), or -(-OC ２ H ４ ) １－１０ -CH ３ is selected from R ２３ is hydrogen, R ２４ But, -C １－５ Alkyl, -C ２－５ Alkenyl, -C ２－５ Alkynyl, —C １－５ Alkyl-N(R ２５ ) (R ２６ ), -C １－５ Alkyl-O-C １－３ Alkyl, -(-C ２ H ４ O) １－１０ C ２ H ５ , -(-C ２ H ４ O) １－１０ -C ２ H ４ -R ２７ , or -C １－３ Alkyl-Het ３ -(-C ２ H ４ O) １－１０ -C ２ H ４ -R ２８ , or 【Chemical 77】 is selected from R ２５ is hydrogen or C1-C3 alkyl, R ２６ is hydrogen or C1-C3 alkyl, or R ２５ and R ２６ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring, wherein one or two carbon atoms in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 5- to 6-membered heterocyclyl ring is unsubstituted or １－３ substituted with alkyl, halogen, or —OH; R ２７ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from R ２８ is hydrogen or —C(O)NH—C ２－５ Alkyl-N(CH ３ ) ２ is selected from Het ３ is a 5- to 10-membered heterocyclyl ring containing 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or R ２３ and R ２４ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring, wherein one or two carbons in said heterocyclyl ring are optionally replaced with additional heteroatoms independently selected from nitrogen, oxygen, and sulfur, and said 4- to 6-membered heterocyclyl ring is unsubstituted or １－３ Alkyl, —N(CH ３ ) ２ , or -CH ２ N (CH ３ ) ２ The ligand-drug conjugate is substituted with

64. R １ but, 【Transformation 78】 and n is 1, R ２ but, 【Chemistry 79】 and R ３ is hydrogen, R ４ But, -C ３ H ６ - and A is val-cit, 【Chemistry 80】 but, 【Chemistry 81】 64. The compound of claim 63, wherein: 【Request Item 65】 【Table 1-1】 Table 1-2 Table 1-3 Table 1-4 Table 1-5 Table 1-6 Table 1-7 Table 1-8 Table 1-9 Table 1-10 Table 1-11 Table 1-12 Table 1-13 Table 1-14 Table 1-15 Table 1-16 Table 1-17 Table 1-18 A compound selected from:

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