Traceless linker and protein conjugate thereof

Abstract

The invention relates to a traceless linker and a protein conjugate thereof. The present invention provides compounds, compounds including traceless linkers, protein conjugates thereof, and compositions thereof. The present invention also provides methods for treating, and / or controlling the symptoms of, diseases, disorders, and conditions associated with, and / or controlling the symptoms of, inflammatory diseases and autoimmune diseases further associated with glucocorticoid receptor, glucocorticoid binding, and / or glucocorticoid receptor signaling, comprising administering the compound or payload via a traceless linker-payload, and protein conjugates thereof.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims and benefits from U.S. Provisional Application No. 62 / 872,229, filed on July 9, 2019; U.S. Provisional Application No. 62 / 937,721, filed on November 19, 2019; PCT Patent Application No. PCT / US2019 / 012786, entitled “Steroids and Antibody Conjugates Thereof,” filed on January 8, 2019; and U.S. Patent Application No. 16 / 243,020, entitled “Steroids and Antibody Conjugates Thereof,” also filed on January 8, 2019. The contents of each priority patent application are incorporated herein by reference in their entirety for all purposes. Field of the Invention

[0002] The present invention provides novel scarless linkers and protein conjugates thereof, as well as methods for treating various diseases, disorders and conditions comprising administering a compound or payload via a scarless linker-payload, and protein conjugates thereof. Background of the Invention

[0003] Antibody-drug conjugates (ADCs) are antibodies covalently linked to a bioactive small molecule drug (often called a payload), thereby combining the targeting specificity of the antibody with the mode of action and potency of the small molecule drug. The therapeutic role of ADCs has been demonstrated in cancer treatment and is a major focus of ongoing research. (bentruximab vedotin) and (ado-trastuzumab emtansine conjugate) are ADCs approved for the treatment of certain cancer types, and several other ADCs are currently in clinical development.

[0004] Glucocorticoids (GC) are small molecule steroids that bind to glucocorticoid receptors (GR) and can be used for anti-inflammatory and immunosuppressive therapies. However, due to the ubiquitous expression of glucocorticoid receptors in many cell types, glucocorticoid therapy is impaired by toxicity to most organ systems. Therefore, new glucocorticoids and new therapies that minimize the side effects caused by glucocorticoid administration (particularly those caused by activating glucocorticoid receptors in non-target cells) are needed. The present invention provides solutions to the above-mentioned needs and other unmet needs in the field to which the present invention belongs. The present invention includes antibody-drug conjugates containing glucocorticoid payloads.

[0005] Liver X receptors (LXRs), including LXRα and LXRβ, are ligand-dependent transcription factors that control the expression of genes involved in cholesterol, lipid, and glucose homeostasis, inflammation, and innate immunity. LXRα is highly expressed in the liver, intestine, adipose tissue, and differentiated macrophages; whereas LXRβ is ubiquitously expressed. LXRs have multiple biological functions, including: (i) stimulating the expression of cholesterol transporters (e.g., ABCA1 and ABCG1), both of which mediate cellular cholesterol efflux; and (ii) negatively regulating macrophage inflammatory gene expression by inhibiting NF-κB activation. LXRs are also implicated in atherosclerosis, proliferative diseases, neurodegenerative diseases, and inflammation. The development of ADCs containing LXR modulators would allow for targeted and specific modulation of LXRs, thereby avoiding side effects caused by off-target modulation of LXRs. Furthermore, such ADCs would provide improved modulation of biological targets, improved bioavailability, and an improved therapeutic window. Therefore, there is a continuing need for small molecule ADCs that are LXR modulators to effectively treat, for example, metabolic diseases.

[0006] A linker covalently links a payload moiety (e.g., a small molecule therapeutic for an ADC) to its antibody. A significant challenge in linker design is finding a group moiety that can maintain a stable attachment of the payload to the antibody during patient storage, formulation, administration, and plasma circulation, yet allow for efficient release when the antibody binds to its target, thereby enabling easy coupling to the payload under synthetic conditions and allowing for release of the intended payload without structural alteration. There is a continuing need for linkers with these and other properties. Abstract

[0007] The present invention provides novel traceless linkers, protein conjugates thereof, and methods for treating a variety of diseases, disorders, and conditions, comprising administering a compound or payload via a traceless linker-payload, and protein conjugates thereof. The present invention includes linkers that attach to a hydroxyl group of a payload and allow the payload to release its intact hydroxyl group under appropriate conditions.

[0008] The present invention provides compounds, compositions and methods for treating a subject, for example, inflammatory diseases and autoimmune diseases, or for controlling the symptoms of any disease, disorder or condition associated with the glucocorticoid receptor, glucocorticoid binding and / or glucocorticoid receptor signaling; and / or dyslipidemia, metabolic diseases, inflammation, or neurodegenerative diseases.

[0009] In one embodiment, the present invention provides a compound having a structure shown in Formula I: or a pharmaceutically acceptable salt thereof, wherein R1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 It is O, NR 6 , or S; R 6 is H, or alkyl; D* is acyl, or the residue of a biologically active compound containing a hydroxyl, amino, or thiol group; and n is 0, 1, 2, 3, 4, 5, or 6.

[0010] In one embodiment, the present invention provides a compound having a structure shown in Formula I: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2To form the heterocyclic group composed of 4, 5, or 6 atoms; R 4 is H or alkyl; R 5 It is O, NR 6 , or S; R 6 is H, or alkyl; D* is acyl, or the residue of a biologically active compound containing a hydroxyl, amino, or thiol group; and n is 0, 1, 2, 3, 4, or 5.

[0011] In another embodiment, the present invention provides a linker-payload compound having the structure shown in Formula II: or a pharmaceutically acceptable salt thereof, wherein L is a linker comprising a moiety reactive with an antibody or antigen-binding fragment thereof; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 It is O, NR 6 , or S; R 6 is H, or alkyl; D* is acyl, or the residue of a biologically active compound containing a hydroxyl, amino, or thiol group; and n is 0, 1, 2, 3, 4, 5, or 6.

[0012] In another embodiment, the present invention provides a linker-payload having the structure shown in Formula II: or a pharmaceutically acceptable salt thereof, wherein L is a linker comprising a moiety reactive with an antibody or antigen-binding fragment thereof; R 1a and R 1bare independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 4, 5, or 6 atoms; R 4 is H or alkyl; R 5 It is O, NR 6 , or S; R 6 is H, or alkyl; D* is acyl, or the residue of a biologically active compound containing a hydroxyl, amino, or thiol group; and n is 0, 1, 2, 3, 4, 5, or 6.

[0013] In another embodiment, the present invention provides a compound having a structure shown in Formula III: Where L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4is H or alkyl; R 5 It is O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

[0014] In another embodiment, the present invention provides a compound having a structure shown in Formula III: Where L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 It is O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of an anti-inflammatory bioactive compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

[0015] In another embodiment, the present invention provides a compound having a structure shown in Formula III: Wherein L is a linker comprising PAB or PABC; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 It is O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

[0016] In another embodiment, the present invention provides a compound having a structure shown in Formula III: Where L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 It is O, NR 6 , or S; R 6is H, or alkyl; D* is the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; wherein the conjugation of L to BA is selected from the group consisting of: a click chemistry residue, an amide residue, and a residue comprising two cysteine ​​residues of a single BA chemically bonded to L; and k is an integer from 1 to 30.

[0017] In another embodiment, the present invention provides a compound having a structure shown in Formula III: Where L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 4, 5, or 6 atoms; R 4 is H or alkyl; R 5 It is O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

[0018] In another embodiment, the present invention provides a method for treating a disease, disorder, or condition associated with glucocorticoid receptor signaling in a subject, comprising administering to the subject an effective amount of a compound, linker-payload, antibody-drug conjugate, pharmaceutical composition, and / or a combination thereof, as described herein.

[0019] In another embodiment, the present invention provides a method for treating dyslipidemia, a metabolic disease, an inflammatory disease, or a neurodegenerative disease in a subject, comprising administering to the subject an effective amount of a compound, a linker-payload, an antibody-drug conjugate, a pharmaceutical composition, and / or a combination thereof, as described herein.

[0020] In another embodiment, the present invention provides a method for treating dyslipidemia in a subject, comprising administering to the subject an effective amount of a compound, linker-payload, antibody-drug conjugate, pharmaceutical composition, and / or combination thereof, as described herein.

[0021] In another embodiment, the present invention provides a method for treating a metabolic disease in a subject, comprising administering to the subject an effective amount of a compound, linker-payload, antibody-drug conjugate, pharmaceutical composition, and / or combination thereof, as described herein.

[0022] In another embodiment, the present invention provides a method for treating inflammation in a subject, comprising administering to the subject an effective amount of a compound, linker-payload, antibody-drug conjugate, pharmaceutical composition, and / or combination thereof, as described herein.

[0023] In another embodiment, the present invention provides a method for treating a neurodegenerative disease in a subject, comprising administering to the subject an effective amount of a compound, linker-payload, antibody-drug conjugate, pharmaceutical composition, and / or combination thereof, as described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1-9 Synthetic chemistry schemes for payloads, prodrugs, scarless linkers, scarless linker-payloads, and protein conjugates thereof are shown. DETAILED DESCRIPTION definition

[0025] When referring to compound provided by the invention, unless otherwise stated, the following terms have the following meanings. Unless otherwise defined, all technical terms and scientific terms used in the present invention all have the identical meaning commonly understood by those of ordinary skill in the art. In the case where there are multiple definitions in the term provided by the invention, unless otherwise stated, these definitions shall prevail.

[0026] As used herein, "alkyl" refers to a monovalent and saturated hydrocarbon group. Alkyl groups are optionally substituted and can be straight chain, branched chain, or cyclic (i.e., cycloalkyl). Alkyl groups include, but are not limited to, groups having 1 to 20 carbon atoms, i.e., C 1-20 Alkyl; 1-12 carbon atoms, i.e. C 1-12Alkyl; 1-8 carbon atoms, i.e. C 1-8 Alkyl; 1-6 carbon atoms, i.e. C 1-6 Alkyl; and 1-3 carbon atoms, i.e. C 1-3 Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, pentyl groups, hexyl groups, cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Pentyl groups include, but are not limited to, n-pentyl and isopentyl. Hexyl groups include, but are not limited to, n-hexyl.

[0027] As used herein, "alkylene" refers to a divalent alkyl group. Unless otherwise indicated, alkylene includes, but is not limited to, 1-20 carbon atoms. Alkylene groups are optionally substituted as described herein for alkyl groups. In some embodiments, alkylene is unsubstituted. Examples of alkylene moieties include -CH2-, -CH2CH2-, -CH2CH2CH2-, -CH2CH2CH2CH2-, etc.

[0028] " heteroalkylene " used in the present invention refers to a divalent alkyl group in which one or more carbon atoms are replaced by heteroatoms. Unless otherwise indicated, heteroalkylene includes but is not limited to a total of 1-20 atoms (i.e., carbon atoms and heteroatoms). The heteroalkylene group is optionally substituted as described for alkyl in the present invention. In some embodiments, heteroalkylene is unsubstituted. In some embodiments, the heteroatoms encompassed in the heteroalkylene group portion include O, N, S (i.e., including sulfoxide, sulfite, sulfate and sulfone), Si and P (i.e., including phosphite and phosphate), and / or combinations thereof. Non-limiting exemplary embodiments of heteroalkylene moieties include -CH2O-, -CH2OCH2-, -CH2OCH2CH2-, -CH2CH2CH2OCH2-, and the like; -CH2NR-, -CH2NRCH2-, -CH2NRCH2CH2-, -CH2CH2CH2NRCH2-, and the like; and -CH2S-, -CH2SCH2-, -CH2SCH2CH2-, -CH2CH2CH2SCH2-, and the like.

[0029] In the absence of designation of its stereochemistry, the name of an amino acid or amino acid residue is intended to encompass the L-form of the amino acid, the D-form of the amino acid, or a racemic mixture thereof.

[0030] As used herein, "haloalkyl" refers to an alkyl group as defined above, wherein the alkyl group includes at least one substituent selected from halogen, such as fluorine (F), chlorine (Cl), bromine (Br), or iodine (I). Examples of haloalkyl groups include, but are not limited to, -CF3, -CH2CF3, -CCl2F, -CHF2, and -CCl3.

[0031] As used herein, "alkenyl" refers to a monovalent hydrocarbon radical moiety containing at least two carbon atoms and one or more non-aromatic carbon-carbon double bonds. Alkenyl groups are optionally substituted and can be straight-chain, branched, or cyclic. Alkenyl groups include, but are not limited to, groups having 2-20 carbon atoms, i.e., C 2-20 Alkenyl; 2-12 carbon atoms, i.e. C 2-12 Alkenyl; 2-8 carbon atoms, i.e. C 2-8 Alkenyl; 2-6 carbon atoms, i.e. C 2-6 Alkenyl; and 2-4 carbon atoms, i.e. C 2-4 Examples of alkenyl moieties include, but are not limited to, ethenyl, propenyl, butenyl, and cyclohexenyl.

[0032] As used herein, "alkynyl" refers to a monovalent hydrocarbon radical moiety containing at least two carbon atoms and one or more carbon-carbon triple bonds. Alkynyl groups are optionally substituted and can be straight-chain, branched, or cyclic. Alkynyl groups include, but are not limited to, groups having 2-20 carbon atoms, i.e., C 2-20 Alkynyl; 2-12 carbon atoms, i.e. C 2-12 Alkynyl; 2-8 carbon atoms, i.e. C 2-8 Alkynyl; 2-6 carbon atoms, i.e. C 2-6 Alkynyl; and 2-4 carbon atoms, i.e., C 2-4 Examples of alkynyl moieties include, but are not limited to, ethynyl, propynyl, and butynyl.

[0033] As used herein, "alkoxy" refers to a monovalent and saturated hydrocarbon moiety wherein the hydrocarbon includes a single bond to an oxygen atom, and wherein the free radical is located on the oxygen atom, such as ethoxy CH3CH2-O. Alkoxy substituents are attached to the compound they replace via the oxygen atom of the alkoxy substituent. Alkoxy groups are optionally substituted and can be straight chain, branched, or cyclic, i.e., cycloalkoxy groups. Alkoxy groups include, but are not limited to, groups having 1-20 carbon atoms, i.e., C 1-20 Alkoxy; 1-12 carbon atoms, i.e. C 1-12 Alkoxy; 1-8 carbon atoms, i.e. C 1-8 Alkoxy; 1-6 carbon atoms, i.e. C 1-6 Alkoxy; and 1-3 carbon atoms, namely C 1-3 Examples of alkoxy moieties include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, isobutoxy, pentoxy moieties, hexoxy moieties, cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, and cyclohexyloxy.

[0034] As used herein, "haloalkoxy" refers to an alkoxy group as defined above, wherein the alkoxy group includes at least one substituent selected from halogen, such as F, Cl, Br or I.

[0035] As used herein, "aryl" refers to a monovalent moiety that is an atomic radical of an aromatic compound wherein the ring atoms are all carbon atoms. Aryl groups are optionally substituted and may be monocyclic or polycyclic, such as bicyclic or tricyclic. Examples of aryl moieties include, but are not limited to, moieties having 6 to 20 ring carbon atoms, i.e., C 6-20 Aryl; 6 to 15 ring carbon atoms, i.e. C 6-15 Aryl, and 6 to 10 ring carbon atoms, namely C 6-10 Examples of aryl moieties include, but are not limited to, phenyl, naphthyl, fluorenyl, azulenyl, anthracenyl, phenanthrenyl, and pyrenyl.

[0036] As used herein, "arylalkyl" or "aralkyl" refers to the monovalent radical portion of an alkyl radical, wherein the alkyl radical is substituted with an aromatic substituent, i.e., the aromatic radical includes a single bond to the alkyl radical, and wherein the radical is located on the alkyl radical. The aralkyl radical is attached to the chemical structure shown via the alkyl radical. Aralkyl groups can be represented by the following structures, for example, Wherein B is an aromatic group part, for example aryl or phenyl.Aralkyl is optionally substituted, i.e., the aryl group and / or the alkyl group can be substituted as described in the present invention. The example of aralkyl includes but is not limited to benzyl.

[0037] As used herein, "alkylaryl" refers to a monovalent radical portion of an aryl radical, wherein the aryl radical is substituted with an alkyl substituent, i.e., the aryl radical includes a single bond to an alkyl radical, wherein the radical is located on the aryl radical. The alkylaryl radical is attached to the chemical structure shown via the aryl radical. An alkylaryl radical can be represented by the following structure, for example, Wherein B is an aromatic group part, for example phenyl.Alkylaryl is optionally substituted, i.e., the aryl group and / or the alkyl group may be substituted as described herein. Examples of alkylaryl include, but are not limited to, toluoyl.

[0038] As used herein, "aryloxy" refers to a monovalent moiety of an aromatic radical wherein the ring atoms are all carbon atoms, and wherein the ring is substituted with an oxy group, i.e., the aromatic compound includes a single bond to an oxygen atom, and wherein the free radical is located on the oxygen atom, e.g., phenoxy. The aryloxy substituents are attached to the compound they replace via this oxygen atom. The aryloxy group is optionally substituted. Aryloxy groups include, but are not limited to, groups having 6 to 20 ring carbon atoms, i.e., C6-20 Aryloxy; 6 to 15 ring carbon atoms, i.e. C 6-15 aryloxy, and 6 to 10 ring carbon atoms, namely C 6-10 Examples of aryloxy moieties include, but are not limited to, phenoxy, naphthoxy, and anthracenoxy.

[0039] As used herein, "arylene" refers to a divalent radical portion of an aromatic compound wherein the ring atoms are exclusively carbon atoms. Arylene is optionally substituted and may be monocyclic or polycyclic, e.g., bicyclic or tricyclic. Examples of arylene moieties include, but are not limited to, moieties having 6 to 20 ring carbon atoms, i.e., C 6-20 Arylene; 6 to 15 ring carbon atoms, i.e. C 6-15 Arylene; and 6 to 10 ring carbon atoms, namely C 6-10 Those of arylene groups.

[0040] As used herein, "heteroalkyl" refers to an alkyl group in which one or more carbon atoms are replaced by a heteroatom. "Heteroalkenyl" refers to an alkenyl group in which one or more carbon atoms are replaced by a heteroatom. "Heteroalkynyl" refers to an alkynyl group in which one or more carbon atoms are replaced by a heteroatom. Suitable heteroatoms include, but are not limited to, nitrogen, oxygen, and sulfur atoms. Heteroalkyl, heteroalkenyl, and heteroalkynyl groups are all optionally substituted. Examples of heteroalkyl moieties include, but are not limited to, aminoalkyl, sulfonylalkyl, and sulfinylalkyl. Examples of heteroalkyl moieties also include, but are not limited to, methylamino, methylsulfonyl, and methylsulfinyl.

[0041] As used herein, "heteroaryl" refers to a monovalent radical portion of an aromatic compound radical wherein the ring atoms contain carbon atoms and at least one oxygen, sulfur, nitrogen, or phosphorus atom. Examples of heteroaryl moieties include, but are not limited to, those having 5 to 20 ring atoms, 5 to 15 ring atoms, and 5 to 10 ring atoms. Heteroaryl groups are optionally substituted.

[0042] As used herein, "heteroarylene" refers to a divalent heteroaryl group in which one or more ring atoms of the aromatic ring are replaced by oxygen, sulfur, nitrogen, or phosphorus atoms. The heteroarylene group is optionally substituted.

[0043] "Heterocycloalkyl" or "heterocyclyl" used in the present invention refers to a cycloalkyl group in which one or more carbon atoms are replaced by heteroatoms. Suitable heteroatoms include, but are not limited to, nitrogen, oxygen, and sulfur atoms (i.e., including sulfoxide and sulfone). Heterocycloalkyl is optionally substituted. Heterocycloalkyl or heterocyclyl is optionally substituted. Examples of heterocycloalkyl and heterocyclyl moieties include, but are not limited to, morpholinyl, piperidinyl, tetrahydropyranyl, pyrrolidinyl, aziridine, imidazolidinyl, oxazolidinyl, thiazolidinyl, dioxolane, dithiolanyl, tetrahydropyranyl (oxanyl) or tetrahydrothiopyranyl (thianyl).

[0044] As used herein, "Lewis acid" refers to a molecule or ion that accepts a lone pair of electrons. The Lewis acids used in the method of the present invention are those other than protons. Lewis acids include, but are not limited to, non-metallic acids, metallic acids, hard Lewis acids, and soft Lewis acids. Lewis acids include, but are not limited to, Lewis acids of aluminum, boron, iron, tin, titanium, magnesium, copper, antimony, phosphorus, silver, ytterbium, scandium, nickel, and zinc. Exemplary Lewis acids include, but are not limited to: AlBr3, AlCl3, BCl3, boron trichloride methyl sulfide, BF3, boron trifluoride methyl ether complex, boron trifluoride methyl sulfide, boron trifluoride tetrahydrofuran, dicyclohexylboron trifluoromethanesulfonate, iron (III) bromide, iron (III) chloride, tin (IV) chloride, titanium (IV) chloride, isopropyl titanate (IV), Cu(OTf)2, CuCl2, CuBr2, zinc chloride, alkylaluminum halides (R n AlX 3-n , wherein R is a hydrocarbon group), Zn(OTf)2, ZnCl2, Yb(OTf)3, Sc(OTf)3, MgBr2, NiCl2, Sn(OTf)2, Ni(OTf)2, and Mg(OTf)2.

[0045] As used herein, "N-containing heterocycloalkyl" refers to a cycloalkyl group in which one or more carbon atoms are replaced by heteroatoms, and in which at least one of the replacing heteroatoms is a nitrogen atom. Suitable heteroatoms include, but are not limited to, oxygen atoms and sulfur atoms, in addition to nitrogen atoms. N-containing heterocycloalkyl groups are optionally substituted. Examples of N-containing heterocycloalkyl groups include, but are not limited to, morpholinyl, piperidinyl, pyrrolidinyl, imidazolidinyl, oxazolidinyl, or thiazolidinyl.

[0046] As used herein, "optionally substituted" or "optionally substituted" when used to describe a moiety, such as an optionally substituted alkyl, means that the moiety is optionally attached to one or more substituents. Examples of such substituents include, but are not limited to, halogen, cyano, nitro, amino, hydroxy, optionally substituted haloalkyl, aminoalkyl, hydroxyalkyl, azido, epoxy, optionally substituted heteroaryl, optionally substituted heterocycloalkyl, where R A 、R B and R C Each occurrence is independently a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkylaryl group, an aralkyl group, a heteroalkyl group, a heteroaryl group, or a heterocycloalkyl group, or R A and R BSaturated or unsaturated carbocycle is formed together with the atom connected thereto, wherein the ring is optionally substituted, and wherein one or more ring atoms are optionally replaced by heteroatoms.In certain embodiments, when group moiety is optionally replaced by the optionally substituted heteroaryl, the optionally substituted heterocycloalkyl or the optionally substituted saturated or unsaturated carbocycle, the substituent on the optionally substituted heteroaryl, the optionally substituted heterocycloalkyl or the optionally substituted saturated or unsaturated carbocycle, if they are substituted, then not further optionally replaced by the substituent replaced by other substituent.In some embodiments, when group of the present invention is optionally substituted, unless otherwise indicated, the substituent connected with the group is unsubstituted.

[0047] As used herein, "binding agent" refers to any molecule, such as a protein, antibody, or fragment thereof, that is capable of specifically binding to a given binding partner (eg, an antigen).

[0048] As used herein, a "linker" refers to a divalent, trivalent, or multivalent moiety that covalently links or is capable of covalently linking (e.g., via an active group) the binding agent to one or more compounds described herein (e.g., the payload compounds and enhancers described herein).

[0049] As used herein, "amide synthesis conditions" refer to reaction conditions suitable for promoting the formation of amides, for example, by reacting a carboxylic acid, an activated carboxylic acid, or an acyl halide with an amine. In some embodiments, "amide synthesis conditions" refer to reaction conditions suitable for promoting the formation of an amide bond between a carboxylic acid and an amine. In some of these embodiments, the carboxylic acid is first converted to an activated carboxylic acid, which is then reacted with the amine to form an amide. Suitable conditions for achieving amide formation include, but are not limited to, those utilizing reagents for achieving the reaction between carboxylic acids and amines, including, but not limited to, dicyclohexylcarbodiimide (DCC), diisopropylcarbodiimide (DIC), (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP), (benzotriazol-1-yloxy)tripyrrolidinylphosphonium hexafluorophosphate (PyBOP), (7-azobenzotriazol-1-yloxy)tripyrrolidinylphosphonium hexafluorophosphate (PyAOP), tripyrrolidinylphosphonium bromide hexafluorophosphate (PyBrOP), O-(benzotriazol-1-yl)-N,N,N',N'-tetramethylurea. Hexafluorophosphate (HBTU), O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluoroborate (TBTU), 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate (HATU), 2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline (EEDQ), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), 2-chloro-1,3-dimethylimidazolium hexafluorophosphate (CIP), 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT), and carbonyldiimidazole (CDI). In some embodiments, the carboxylic acid is first converted to an activated carboxylate, and the activated carboxylate is then treated with an amine to form an amide bond. In some embodiments, the carboxylic acid is treated with a reagent. The reagent activates the carboxylic acid by deprotonating the carboxylic acid, and then forms a product complex with the deprotonated carboxylic acid due to the nucleophilic attack of the deprotonated carboxylic acid. For some carboxylic acids, before the carboxylic acid is converted into an activated ester, the activated carboxylic acid ester is more susceptible to the nucleophilic attack of amine. This makes amide bonds form. Therefore, the carboxylic acid is described as activated. Exemplary reagents include DCC and DIC.

[0050] As used herein, a "regioisomer" or "mixture of regioisomers" refers to a 1,3-cycloaddition product or a strain-promoted alkyne-azide cycloaddition product (SPAAC) (also known as a click reaction) resulting from treatment of a suitable azide (e.g., a -N3 or PEG-N3 derivatized antibody) with a suitable alkyne compound. In certain embodiments, for example, the regioisomers and mixtures of regioisomers are characterized by a click reaction product as shown below: In certain embodiments, more than one suitable azide and more than one suitable alkyne can be used in a synthetic scheme to generate a product, wherein each azide-alkyne pair can participate in one or more independent click reactions to generate a mixture of regioisomeric click reaction products. For example, one skilled in the art will recognize that a first suitable azide can be independently reacted with a first suitable alkyne, and a second suitable azide can be independently reacted with a second suitable alkyne en route to the product, thereby generating four possible click reaction regioisomers or a mixture of the four possible click reaction regioisomers.

[0051] As used herein, the term "residue" refers to the portion of a chemical group that remains after a chemical reaction within a compound. For example, the term "amino acid residue" or "N-alkyl amino acid residue" refers to the product of amide coupling or peptide coupling of an amino acid or N-alkyl amino acid with a suitable coupling partner; wherein, for example, water molecules are expelled following the amide coupling or peptide coupling of the amino acid or N-alkyl amino acid, resulting in the product in which the amino acid residue or N-alkyl amino acid residue is incorporated.

[0052] As used herein, a "therapeutically effective amount" refers to an amount (e.g., of a compound) sufficient to provide a therapeutic benefit in treating or managing a disease or condition, or delaying or minimizing one or more symptoms associated with a disease or condition.

[0053] As used herein, "constitutional isomers" refer to compounds that have the same molecular formula but differ in chemical structure due to the arrangement of their atoms. Exemplary constitutional isomers include n-propyl and isopropyl; n-butyl, sec-butyl, and tert-butyl; and n-pentyl, isopentyl, and neopentyl.

[0054] Certain groups, molecules / group moieties, substituents, and atoms are depicted with a wavy line intersecting a bond to indicate the atom through which the group, molecule / group moiety, substituent, atom is attached. For example, a phenyl group substituted with a propyl group can be represented as: Has the following structure: As used herein, the illustrative description of substituents attached to cyclic groups (e.g., aromatic rings, heteroaromatic rings, fused rings, and saturated or unsaturated cycloalkyl or heterocycloalkyl) through bonds between ring atoms is intended to indicate that, unless otherwise indicated, the cyclic group may be substituted with a substituent at any ring position of the cyclic group or on any ring of a fused ring group according to the techniques described herein or immediately disclosed techniques known in the art. For example, the group wherein the subscript q is an integer from 0 to 4, and wherein the substituent R 1The positions of are generally described, i.e., not directly connected to any vertex of the bond line structure, i.e., a specific ring carbon atom, including the following, where the substituent R 1 Non-limiting examples of groups attached to specific ring carbon atoms:

[0055] As used herein, the phrase "reactive linker" or the abbreviation "RL" refers to a monovalent group comprising a reactive group ("RG") and a spacer group ("SP"), such as As shown, RG is the active group and SP is the spacer group. As described herein, an active (reactive) linker may comprise one or more active (reactive) groups and one or more spacer groups. The spacer group is any divalent moiety that bridges the active (reactive) group to another group, such as a payload (e.g., a biologically active compound). The active linker (RL), together with the payload to which it is attached, constitutes an intermediate ("linker-payload" or LP) that can be used as a synthetic precursor for preparing the antibody conjugates described herein. The active linker comprises an active group, which is a functional group or moiety that is capable of reacting with the active moiety of another group (e.g., an antibody, a modified antibody, or an antigen-binding fragment thereof, or an enhancing group). The moiety resulting from the reaction of the active group with the antibody, modified antibody, or antigen-binding fragment thereof, together with the linker group, constitutes the "binder linker" ("BL") portion of the conjugate described herein. In certain embodiments, the "active group" is a functional group or group portion that reacts with a cysteine ​​or lysine residue of an antibody or antigen-binding fragment thereof (e.g., maleimide or N-hydroxysuccinimide (NHS) ester). In certain embodiments, the "active group" is a functional group or group portion that can undergo click chemistry (see, e.g., click chemistry, Huisgen Proc. Chem. Soc. 1961, Wang et al. J. Am. Chem. Soc. 2003, and Agard et al. J. Am. Chem. Soc. 2004). In some embodiments of the click chemistry reaction, the active group is an alkyne that can undergo a 1,3-cycloaddition reaction with an azide. Such suitable reactive groups include, but are not limited to, strained alkynes, such as those suitable for strain-promoted alkyne-azide cycloaddition (SPAAC), cycloalkynes, such as cyclooctynes, benzoannulated alkynes, and alkynes capable of undergoing 1,3-cycloaddition reactions with alkyne compounds in the absence of a copper catalyst. Suitable alkynes also include, but are not limited to Cyclooctyne Azacyclooctyne dibenzazepine octyne or dibenzocyclooctyne or diaryl azacyclooctynyl ketone or Monofluorinated cyclooctyne Difluorinated cyclooctyne or Substituted, such as fluorinated alkynes, azacyclic alkynes, bicyclo[6.1.0]nonyne or (BCN, where R is alkyl, alkoxy, or acyl), and their derivatives. Particularly useful alkynes include Linker-payloads comprising such reactive groups can be used to couple antibodies that have been functionalized with an azide group. Such functionalized antibodies include antibodies functionalized with an azide-polyethylene glycol group. In certain embodiments, such functionalized antibodies are derived by treating an antibody having at least one glutamine residue (e.g., heavy chain Gln295) with a compound bearing an amino group and an azide group in the presence of the enzyme transglutaminase.

[0056] In some embodiments, the reactive group is an alkyne, for example It can be synthesized by click chemistry with azides (e.g. ) reaction to form click chemistry products, such as In some embodiments, the group reacts with an azide on the modified antibody or antigen-binding fragment thereof. In some embodiments, the reactive group is an alkyne, such as It can be synthesized by click chemistry with azides (e.g. ) reaction to form click chemistry products, such as In some embodiments, the reactive group is an alkyne, for example It can be synthesized by click chemistry with azides (e.g. ) reaction to form click chemistry products, such as In some embodiments, the reactive group is a functional group, such as It reacts with cysteine ​​residues on antibodies or antigen-binding fragments thereof to form CS bonds therewith, e.g. Wherein Ab refers to an antibody or an antigen-binding fragment thereof, S refers to the S atom on a cysteine ​​residue, and the functional group is bound to Ab via the S atom on the cysteine ​​residue. In some embodiments, the active group is a functional group, for example It reacts with lysine residues on antibodies or antigen-binding fragments thereof to form amide bonds therewith, e.g. Wherein Ab refers to an antibody or an antigen-binding fragment thereof, NH refers to the NH atom on a lysine side chain residue, and the functional group is bound to Ab via the NH atom on the lysine side chain residue.

[0057] As used herein, the phrase "biodegradable moiety" refers to a moiety that degrades in vivo into non-toxic, biocompatible components that can be eliminated from the body by normal biological processes. In some embodiments, the biodegradable moiety completely or substantially degrades in vivo within about 90 days or less, about 60 days or less, or about 30 days or less, wherein the extent of degradation is based on the percent loss of mass of the biodegradable moiety, where complete degradation corresponds to 100% mass loss. Exemplary biodegradable moieties include, but are not limited to, aliphatic polyesters such as poly(ε-caprolactone) (PCL), poly(3-hydroxybutyrate) (PHB), poly(glycolic acid) (PGA), poly(lactic acid) (PLA) and copolymers thereof with glycolic acid (i.e., poly(D,L-lactide-co-glycolide) (PLGA) (Vert M, Schwach G, Engel R and Coudane J (1998) J Control Release 53(1-3):85-92; Jain RA (2000) Biomaterials 21(23):2475-2490; Uhrich KE, Cannizzaro SM, Langer RS ​​and Shakesheff KM (1999) Chemical Reviews 99(11):3181-3198; and Park TG (1995) Biomaterials 16(15):1123-1130, the entire contents of each of which are incorporated herein by reference).

[0058] The phrase "binding agent linker" or "BL" as used herein refers to any divalent, trivalent, or multivalent group or moiety that connects, binds, or bonds a binding agent (e.g., an antibody or antigen-binding fragment thereof) to a payload compound (e.g., tubulysin) described herein, and optionally to one or more side chain compounds. Typically, suitable binding agent linkers for the antibody conjugates of the present invention are those that are stable enough to utilize the circulating half-life of the antibody conjugate and, at the same time, are capable of releasing their payload upon antigen-mediated internalization of the conjugate. Linkers may be cleavable or non-cleavable. Cleavable linkers are linkers that are cleaved by intracellular metabolism after internalization, such as by hydrolysis, reduction, or enzymatic reactions. Non-cleavable linkers are linkers that release the attached payload by lysosomal degradation of the antibody after internalization. Suitable linkers include, but are not limited to, acid-labile linkers, hydrolytically unstable linkers, enzymatically cleavable linkers, reduction-labile linkers, self-immolative linkers, and non-cleavable linkers. Suitable linkers also include, but are not limited to, those that are or comprise peptides, glucuronides, succinimide-thioethers, polyethylene glycol (PEG) units, hydrazones, maleimide (mal)-hexanoyl units, dipeptide units, valine-citrulline units, and p-aminobenzyloxycarbonyl (PABC) units, p-aminobenzyl (PAB) units. In some embodiments, the binding agent linker (BL) comprises a group portion formed by reacting the active group (RG) of the active linker (RL) with the active portion of the binding agent (e.g., an antibody, a modified antibody, or an antigen-binding fragment thereof).

[0059] In some embodiments, the BL comprises the following moiety: in is a bond connected to the binding agent. In some embodiments, the BL comprises the following group portion: in is a bond connected to the binding agent. In some embodiments, the BL comprises the following group portion: in is a bond connected to the binding agent. In some embodiments, the BL comprises the following group portion: in is a bond connected to the cysteine ​​of the antibody or antigen-binding fragment thereof. In some embodiments, the BL comprises the following moiety: in is a bond to the lysine of the antibody or antigen-binding fragment thereof.

[0060] As used herein, "amino acid side chain" refers to the chemical group moiety attached to the same carbon that bears the primary or secondary amine and the carboxylic acid of the amino acid. As will be appreciated by those skilled in the art, there are 21 "standard" amino acids. Exemplary "standard" amino acids include, but are not limited to, alanine, serine, proline, arginine, and aspartic acid. Other amino acids include cysteine, selenocysteine, and glycine (e.g., where the chemical group moiety attached to the same carbon that bears the primary amine and the glycine carboxylic acid is hydrogen). Exemplary amino acid side chains include, but are not limited to, methyl (i.e., alanine), sec-butyl (i.e., isoleucine), isobutyl (i.e., leucine), -CH2CH2SCH3 (i.e., methionine), -CH2Ph ​​(i.e., phenylalanine), (i.e. tryptophan), (i.e. tyrosine), isopropyl (i.e. valine), hydroxymethyl (i.e. serine), –CH(OH)CH3 (i.e. threonine), –CH2C(O)NH2 (i.e. asparagine), –CH2CH2C(O)NH2 (i.e. glutamine), –CH2SH (i.e. cysteine), –CH2SeH (i.e. selenocysteine), –CH2NH2 (i.e. glycine), propylene or -CH2CH2CH2- (i.e. proline), –CH2CH2CH2NHC(=NH)NH2 (i.e. arginine), (i.e., histidine), –CH2CH2CH2CH2NH2 (i.e., lysine), –CH2COOH (i.e., aspartic acid), and –CH2CH2COOH (i.e., glutamic acid).

[0061] As used herein, a "biologically active compound" refers to a compound, prodrug, or payload that, when administered to a biological entity, elicits a biological response. Exemplary biological responses include, but are not limited to, increases or decreases in DNA or protein synthesis, upregulation or downregulation of signaling pathways, and increases or decreases in cell proliferation. Compound, prodrug, or payload

[0062] The present invention provides compounds or payloads. Without being bound by any particular theory of operation, the compounds include anti-inflammatory bioactive compounds, steroids, steroid derivatives, and / or LXR modulators, and derivatives thereof, such as prodrugs thereof. The terms or phrases "compound," "bioactive compound," "prodrug," and "payload" are used interchangeably throughout the present invention. In certain embodiments, the bioactive compound (D*) or a residue thereof includes a hydroxyl functional group (e.g., D*-OH or D*-O-R). In certain embodiments of the present invention, for example and for convenience, R 5 represents a hydroxyl, amino, and thiol functional group within the biologically active compounds of the present invention, as understood by the skilled artisan, or a portion thereof, such as -O-, -N(R)-, or -S-. In other words, the skilled artisan will recognize that R5 It can be part of a biologically active compound (e.g., D*) described herein and can be used as a functional group for conjugation purposes. In one embodiment, the hydroxyl functional group is a primary hydroxyl moiety (e.g., D*–CH2OH or D*–CH2O–R; or D*–C(O)CH2OH or D*–C(O)CH2O–R). In another embodiment, the hydroxyl functional group is a secondary hydroxyl moiety (e.g., D*–CH(OH)R or D*–CH(O–R)R; or D*–C(O)CH(R)(OH) or D*–C(O)CH(R)(O–R)). In another embodiment, the hydroxyl functional group is a tertiary hydroxyl moiety (e.g., D*–C(R1)(R2)(OH) or D*–C(R1)(R2)(O–R); or D*–C(O)C(R1)(R2)(OH) or D*–C(O)C(R1)(R2)(O–R)). One skilled in the art will recognize that each of the functional groups in the preceding sentences can be part of the biologically active compound D* and are depicted together in the general formula for clarity, convenience, and / or emphasis. In another embodiment, D* comprising a hydroxyl functional group is an aryl hydroxyl group or a phenolic hydroxyl group (e.g., D*-Ar-OH, D*-Ar-O-R). In one embodiment, the biologically active compound (D*) comprising a hydroxyl functional group (D*-OH) is dexamethasone, and the residue comprising a hydroxyl functional group is in represents a connection to a prodrug moiety (as shown in Formula Ia and / or Ib), a linker and / or a binding agent, as described herein. In one embodiment, the biologically active compound (D*) comprising a hydroxyl functional group is dexamethasone, and the residue comprising a hydroxyl functional group is in represents a connection to a prodrug moiety (as shown in Formula Ia and / or Ib), a linker and / or a binding agent, as described herein. In one embodiment, the biologically active compound (D*) comprising a hydroxyl functional group (D*-OH) is budesonide, and the residue comprising a hydroxyl functional group is in represents a connection to a prodrug moiety (as shown in Formula Ia and / or Ib), a linker and / or a binding agent, as described herein. In one embodiment, the biologically active compound (D*) comprising a hydroxyl functional group is budesonide, and the residue comprising a hydroxyl functional group is in represents a connection to a prodrug moiety (as shown in Formula Ia and / or Ib), a linker and / or a binding agent, as described herein. In one embodiment, the biologically active compound (D*) comprising a hydroxyl functional group (D*-OH) is 6,11-2F-budesonide, and the residue comprising a hydroxyl functional group is in represents a connection to a prodrug moiety (as shown in Formula Ia and / or Ib), a linker and / or a binding agent, as described herein. In one embodiment, the biologically active compound (D*) comprising a hydroxyl functional group is 6,11-2F-budesonide, and the residue comprising a hydroxyl functional group is in represents a connection to a prodrug moiety (as shown in Formula Ia and / or Ib), a linker and / or a binding agent, as described herein. In one embodiment, the biologically active compound (D*) comprising a hydroxyl functional group (D*-OH) is an LXR agonist, and the residue comprising a hydroxyl functional group is in represents a connection to a prodrug moiety (as shown in Formula Ia and / or Ib), a linker and / or a binding agent, as described herein. In one embodiment, the biologically active compound (D*) comprising a hydroxyl functional group is an LXR agonist, and the residue comprising a hydroxyl functional group is in Represents a connection to a prodrug moiety (as shown in Formula Ia and / or Ib), a linker, and / or a binding agent, as described herein. In certain embodiments, the biologically active compound (D*) or a residue thereof includes an amino functional group (e.g., D*-NR2 or D*-N(R)-R). In one embodiment, the amino functional group is a primary amine moiety (e.g., D*-CH2NR2 or D*-CH2N(R)-R; or D*-C(O)CH2NR2 or D*-C(O)CH2N(R)-R). In another embodiment, the amino functional group is a secondary amine moiety (e.g., D*-CH(NR2)R or D*-CH(NR-R)R; or D*-C(O)CH(R)(NR2) or D*-C(O)CH(R)(NR-R)). In another embodiment, the amino functional group is a tertiary amine moiety (e.g., D*-C(R1)(R2)(NR2) or D*-C(R1)(R2)(N(R)-R); or D*-C(O)C(R1)(R2)(NR2) or D*-C(O)C(R1)(R2)(N(R)-R)). In another embodiment, D* comprising an amino functional group is an arylamine (e.g., D*-Ar-NR2, D*-Ar-N(R)-R). In certain embodiments, the biologically active compound (D*) or a residue thereof comprises a thiol functional group (e.g., D*-SH or D*-S-R). In one embodiment, the thiol functional group is a primary thiol moiety (e.g., D*-CH2SH or D*-CH2S-R; or D*-C(O)CH2SH or D*-C(O)CH2S-R). In another embodiment, the thiol functional group is a secondary thiol moiety (e.g., D*-CH(SH)R or D*-CH(S-R)R; or D*-C(O)CH(R)(SH) or D*-C(O)CH(R)(S-R)). In another embodiment, the thiol functional group is a tertiary thiol moiety (e.g., D*-C(R1)(R2)(SH) or D*-C(R1)(R2)(S-R); or D*-C(O)C(R1)(R2)(SH) or D*-C(O)C(R1)(R2)(S-R)). In another embodiment, D* comprising a thiol functional group is an aryl thiol or thiophenol (e.g., D*-Ar-SH, D*-Ar-S-R). In certain embodiments, D* is a tetracyclic or pentacyclic steroidal backbone structure, as will be understood by those skilled in the art. In certain embodiments, the compound can be delivered to a cell as part of a conjugate. In certain embodiments, the compound is capable of performing any activity of a steroid, steroid derivative, LXR modulator, or derivative thereof at or in a target (eg, a target cell). Certain compounds may have one or more additional activities.

[0063] In certain embodiments, the present invention provides a compound having the structure shown in Formula Ia: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, or alkylene, wherein when R 1a When it is an alkylene group, the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, or an amino acid side chain; R 3 is H, alkyl, or alkylene, wherein when R 3 When it is an alkylene group, the alkylene group is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group; and n is 0, 1, 2, 3, 4, or 5.

[0064] In certain embodiments, the present invention provides a compound having the structure shown in Formula Iaa: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 4, 5, or 6 atoms; R 6 is H, or alkyl; D* is acyl, or the residue of a biologically active compound containing an amino group; and n is 0, 1, 2, 3, 4, or 5.

[0065] In certain embodiments, the present invention provides a compound having the structure shown in Formula Iaaa: or a pharmaceutically acceptable salt thereof, wherein R 1a and R1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 to form the 4, 5, or 6-atom heterocyclic group; D* is an acyl group, or the residue of a biologically active compound containing a thiol; and n is 0, 1, 2, 3, 4, or 5.

[0066] In certain embodiments, the present invention provides a compound having the structure shown in Formula Ib: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, or alkylene, wherein when R 1a When it is an alkylene group, the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, or an amino acid side chain; R 3 is H, alkyl, or alkylene, wherein when R 3 When it is an alkylene group, the alkylene group is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group; and n is 0, 1, 2, 3, 4, or 5.

[0067] In certain embodiments, the present invention provides a compound having the structure shown in Formula Ibb: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1aWhen it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 4, 5, or 6 atoms; R 6 is H, or alkyl; D* is acyl, or the residue of a biologically active compound containing an amino group; and n is 0, 1, 2, 3, 4, or 5.

[0068] In certain embodiments, the present invention provides a compound having a structure shown in Formula Ibbb: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 to form the 4, 5, or 6-atom heterocyclic group; D* is an acyl group, or the residue of a biologically active compound containing a thiol; and n is 0, 1, 2, 3, 4, or 5.

[0069] The following embodiments of Formula I and / or Formula Ib are contemplated, wherein in any one or more of the foregoing embodiments, the biologically active compound comprises a hydroxyl group; or in the residue D* of the biologically active compound, in certain embodiments, the residue (i.e., the bond to O) of the hydroxyl group is connected to the remainder of the molecule. In one embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is H; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0070] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is H; and n is 0. In another embodiment, R1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0071] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R4 It is an alkyl group.

[0072] In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0073] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0074] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R1b is an alkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0075] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0076] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; in another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0077] In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0078] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0079] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1bis an alkoxy group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0080] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is an alkoxy group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0081] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0082] In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0083] In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0084] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0085] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1ato form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 0. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0086] In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1bis an aryl group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1bis heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0087] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0088] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0089] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0090] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1ato form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0091] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0092] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0093] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1bis an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0094] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3is alkyl; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0095] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0096] In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0097] In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1bis heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0098] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3is alkyl; D* is the residue of a biologically active compound; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0099] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In any embodiment of this paragraph, R4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0100] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0101] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 1. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0102] In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0103] In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2It is H; R 3 is alkyl; D* is H; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0104] In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1bis an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0105] In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form the heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1ato form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0106] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0107] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is an alkynyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0108] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0109] In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0110] In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1bis an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0111] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0112] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0113] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0114] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1bis alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0115] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0116] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1ato form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0117] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0118] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 2. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0119] In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R2 It is H; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0120] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is H; and n is 3. In another embodiment, R1a It is H, and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0121] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1aIt is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1bis an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0122] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1ato form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0123] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is H; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0124] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0125] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0126] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1bis alkenyl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0127] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is alkyl; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1ato form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0128] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is acyl; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0129] In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1ais an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0130] In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is H; D* is the residue of a biologically active compound; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0131] In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0132] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R1b is heteroaryl; R 2 It is H; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a It is H, and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is alkyl; D* is the residue of a biologically active compound; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0133] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkyl group; D* is a residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0134] In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b It is H; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1ato form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkoxy group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is alkenyl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an alkynyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aryl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1ato form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is an aralkyl group; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In another embodiment, R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; and R 1b is heteroaryl; R 2 is the amino acid side chain; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5, or 6-atom heterocyclic group; D* is the residue of a biologically active compound; and n is 3. In any embodiment of this paragraph, R 4 is H. In any of the embodiments of this paragraph, R 4 It is an alkyl group.

[0135] In another embodiment, R 1a It is H, and R 1b It is H; R 2 It is H; R 3 is H; D* is H; and n is 4. In another embodiment, R 1a It is H, and R 1b is an alkyl group; R 2 It is H; R 3 is H; D* is H; and n is 4. In another embodiment, R 1a It is H, and R 1b is an alkoxy group; R 2 It is H; R 3 is H; D* is H; and n is 4. In another embodiment, R 1a It is H, and R 1b is alkenyl; R 2 It is H; R 3 is H; D* is H; and n is 4. In another embodiment, R 1a It is H, and R 1b is a...

Claims

1. A compound having the following structure: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; and n is 0, 1, 2, 3, 4, 5, or 6.

2. The compound according to claim 1, having the following structure: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 4, 5, or 6 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; and n is 0, 1, 2, 3, 4, or 5.

3. The compound according to claim 2, having the following structure: or a pharmaceutically acceptable salt thereof, wherein R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, or alkylene, wherein when R 1a When it is an alkylene group, the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, or an amino acid side chain; R 3 is H, alkyl, or alkylene, wherein when R 3 When it is an alkylene group, the alkylene group is further connected to R 1a To form the heterocyclic group composed of 4, 5, or 6 atoms; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group; and n is 0, 1, 2, 3, 4, or 5.

4. The compound according to claim 2, wherein the compound has the following structure:

5. A compound according to any one of the preceding claims, wherein R 1a and R 1b Each is H.

6. A compound according to any one of the preceding claims, wherein n is 2.

7. A compound according to any one of the preceding claims, wherein n is 2, and R 2 It is H or methyl.

8. A compound according to any one of the preceding claims, wherein n is 2, R 2 is H or methyl, R 3 is H, and D* is the residue of a biologically active compound containing a hydroxyl group.

9. The compound according to claim 8, wherein the compound is selected from the group consisting of: or pharmaceutically acceptable salts thereof.

10. The compound according to claim 5, wherein n is 1.

11. The compound according to claim 10, wherein R 2 It is H, methyl, or -CH2Ph.

12. The compound according to claim 11, wherein R 3 It's H.

13. The compound of claim 12, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

14. The compound according to claim 13, wherein the compound is selected from the group consisting of: or or pharmaceutically acceptable salts thereof.

15. The compound according to claim 10, wherein R 2 It is H or methyl.

16. The compound according to claim 15, wherein R 3 It is an alkyl group.

17. The compound of claim 16, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

18. The compound according to claim 17, wherein the compound is selected from the group consisting of: or a pharmaceutically acceptable salt thereof.

19. The compound according to claim 2, wherein R 1a is an alkyl group or an aralkyl group, and R 1b It's H.

20. The compound of claim 19, wherein n is 1.

21. The compound according to claim 20, wherein R 2 It's H.

22. The compound according to claim 21, wherein R 3 It's H.

23. The compound of claim 22, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

24. The compound according to claim 23, wherein the compound is selected from the group consisting of: or a pharmaceutically acceptable salt thereof.

25. The compound according to claim 2, wherein R 1a is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 1b is H; and R 3 is an alkylene group, which is further connected to R 1a To form the heterocyclic group composed of 4, 5, or 6 atoms.

26. The compound of claim 25, wherein n is 1.

27. The compound according to claim 26, wherein R 2 It's H.

28. The compound of claim 27, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

29. The compound according to claim 28, wherein the compound is selected from the group consisting of: or a pharmaceutically acceptable salt thereof.

30. The compound according to claim 10, wherein the compound is 31. The compound of claim 5, wherein the compound is selected from the group consisting of:

32. The compound according to claim 10, wherein R 2 is an alkylene group, wherein the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 6 atoms; and R 3 is an alkylene group, wherein the alkylene group is further connected to R 2 To form the heterocyclic group composed of 6 atoms.

33. The compound of claim 32, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

34. The compound according to claim 33, wherein the compound is or a pharmaceutically acceptable salt thereof.

35. A compound having the following structure: or a pharmaceutically acceptable salt thereof, wherein L is a linker comprising a moiety reactive with the antibody or antigen-binding fragment thereof; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; and n is 0, 1, 2, 3, 4, 5, or 6.

36. The compound of claim 35, wherein when D* is a residue of a biologically active compound comprising a hydroxyl group, an amino group, or a thiol group, then the biologically active compound or residue thereof is an anti-inflammatory biologically active compound or residue thereof.

37. The compound of claim 36, wherein the anti-inflammatory bioactive compound is a steroid or a residue thereof.

38. The compound of claim 36, wherein the anti-inflammatory bioactive compound is an LXR agonist or a residue thereof.

39. The compound according to claim 35, having the following structure: or a pharmaceutically acceptable salt thereof, wherein L is a linker comprising a moiety reactive with the antibody or antigen-binding fragment thereof; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 4, 5, or 6 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; and n is 0, 1, 2, 3, 4, 5, or 6.

40. The compound according to claim 39, having the following structure: or a pharmaceutically acceptable salt thereof, wherein L is a linker comprising a moiety reactive with the antibody or antigen-binding fragment thereof; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, or alkylene, wherein when R 1a When it is an alkylene group, the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, or an amino acid side chain; R 3 is H, alkyl, or alkylene, wherein when R 3 When it is an alkylene group, the alkylene group is further connected to R 1a To form the heterocyclic group composed of 4, 5, or 6 atoms; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group; and n is 0, 1, 2, 3, 4, 5, or 6.

41. The compound according to claim 39, having the following structure: or a pharmaceutically acceptable salt thereof, wherein L is a linker comprising a moiety reactive with the antibody or antigen-binding fragment thereof; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, or alkylene, wherein when R 1a When it is an alkylene group, the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, or an amino acid side chain; R 3 is H, alkyl, or alkylene, wherein when R 3 When it is an alkylene group, the alkylene group is further connected to R 1a To form the heterocyclic group composed of 4, 5, or 6 atoms; D* is an acyl group, or the residue of a biologically active compound containing a hydroxyl group; and n is 0, 1, 2, 3, 4, 5, or 6.

42. The compound according to any one of claims 35-41, wherein the linker further comprises 43. The compound according to claim 39, wherein the compound is or a pharmaceutically acceptable salt thereof, wherein SP 1 and SP 2 , when present, are spacer groups, wherein SP 1 further comprising a moiety reactive with an antibody or antigen-binding fragment thereof; each AA is an amino acid; and P is an integer from 1 to 10.

44. The compound according to claim 43, wherein SP 1 A reactive group is included, wherein the reactive group includes an alkyne.

45. The compound of claim 44, wherein the alkyne is capable of participating in a 1,3-cycloaddition reaction.

46. ​​The compound of claim 35, wherein the alkyne is capable of participating in a 1,3-cycloaddition reaction with an azide to form a regioisomeric 1,2,3-triazolyl moiety, wherein the azide comprises an azide-functionalized binding agent.

47. The compound according to claim 43, wherein SP 2 Include 48. The compound according to claim 43, wherein SP 2 Include and R 2 is H or alkyl.

49. The compound of claim 46, wherein the alkyne is capable of participating in a 1,3-cycloaddition reaction with an azide comprising an azide-functionalized binding agent to form a regioisomeric 1,2,3-triazolyl moiety. 2 Include 50. The compound of claim 46, wherein the alkyne is capable of participating in a 1,3-cycloaddition reaction with an azide comprising an azide-functionalized binding agent to form a regioisomeric 1,2,3-triazolyl moiety. 2 Include and R 2 is H or alkyl.

51. The compound according to claim 43, wherein R 1a and R 1b All are H; R 2 is H or methyl; R 3 is H; and n is 2.

52. The compound of claim 51, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

53. The compound according to claim 52, selected from the group consisting of: or or pharmaceutically acceptable salts thereof.

54. The compound according to claim 43, wherein R 1a and R 1b All are H; R 2 is H, methyl, or -CH2Ph; R 3 is H or alkyl; and n is 1.

55. The compound of claim 54, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

56. The compound according to claim 55, selected from the group consisting of: or a pharmaceutically acceptable salt thereof.

57. The compound according to claim 43, wherein R 1a and R 1b All are H; R 2 It is H; R 3 is an alkyl group; and n is 1.

58. The compound of claim 57, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

59. The compound according to claim 58, having the structure or a pharmaceutically acceptable salt thereof.

60. The compound according to claim 43, wherein R 1a is an alkyl group or an aralkyl group; R 1b It is H; R 2 It is H; R 3 is H; and n is 1.

61. The compound of claim 60, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

62. The compound according to claim 61, selected from the group consisting of: or or pharmaceutically acceptable salts thereof.

63. The compound according to claim 43, wherein R 1a is an alkylene group, which is further connected to R 3 to form a heterocyclic group consisting of 4, 5 or 6 atoms; R 1b It is H; R 2 It is H; R 3 is an alkylene group, which is further connected to R 1a to form the 4, 5 or 6-atom heterocyclic group; and n is 1.

64. The compound of claim 63, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

65. The compound according to claim 64, selected from the group consisting of: or or pharmaceutically acceptable salts thereof.

66. The compound according to claim 64, having the structure or a pharmaceutically acceptable salt thereof.

67. The compound according to claim 39, wherein R 1a and R 1b All are H; R 2 It is H; R 3 is H; and n is 1.

68. The compound of claim 67, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

69. The compound according to claim 68, having the following structure: or a pharmaceutically acceptable salt thereof.

70. The compound according to claim 39, wherein R 1a and R 1b All are H; R 2 is H or -CH2Ph; R 3 is H; and n is 4.

71. The compound of claim 70, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

72. The compound of claim 71 selected from the group consisting of: or a pharmaceutically acceptable salt thereof.

73. The compound according to claim 41, wherein R 1a and R 1b All are H; R 3 is H; and n is 0.

74. The compound of claim 73, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

75. The compound of claim 74 selected from the group consisting of: or a pharmaceutically acceptable salt thereof.

76. The compound according to claim 57, wherein R 1a and R 1b All are H; R 2 It is H; R 3 is an alkyl group; R 4 is an alkyl group; and n is 1.

77. The compound of claim 76, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

78. The compound of claim 77 having the structure: or a pharmaceutically acceptable salt thereof.

79. The compound according to claim 39, wherein R 1a and R 1b All are H; R 2 is H or -CH2OH; R 3 is H; and n is 6.

80. The compound of claim 79, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

81. The compound of claim 80 having the structure: or a pharmaceutically acceptable salt thereof.

82. The compound according to claim 43, wherein R 1a and R 1b All are H; R 2 is an alkylene group, wherein the alkylene group is further connected to R 3 To form a heterocyclic group consisting of 6 atoms; R 3 is an alkylene group, wherein the alkylene group is further connected to R 2 to form the 6-atom heterocyclic group; and n is 1.

83. The compound of claim 82, wherein D* is the residue of a biologically active compound comprising a hydroxyl group.

84. The compound of claim 83, wherein the compound is or a pharmaceutically acceptable salt thereof.

85. The compound of claim 53, wherein the compound is or a pharmaceutically acceptable salt thereof.

86. The compound of claim 53, wherein the compound is or a pharmaceutically acceptable salt thereof.

87. The compound of claim 65, wherein the compound is or a pharmaceutically acceptable salt thereof.

88. The compound of claim 56, wherein the compound is or a pharmaceutically acceptable salt thereof.

89. The compound of claim 56, wherein the compound is or a pharmaceutically acceptable salt thereof.

90. A compound having the following structure: in, L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

91. The compound of claim 90, wherein D* is the residue of an anti-inflammatory bioactive compound comprising a hydroxyl, amino, or thiol group.

92. The compound of claim 91, wherein the anti-inflammatory biologically active compound is a steroid or a residue thereof.

93. The compound of claim 91, wherein the anti-inflammatory bioactive compound is a LXR agonist or a residue thereof.

94. A compound having the following structure: in, L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of an anti-inflammatory bioactive compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

95. The compound of claim 94, wherein D* is the residue of a steroid containing a hydroxyl, amino, or thiol group.

96. A compound having the following structure: in, L is a linker, said linker comprising BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

97. according to the compound described in claim 96, wherein L is comprising The connector, and R 2 It's H.

98. A compound having the following structure: in, L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 3, 4, 5, 6, 7, or 8 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 3, 4, 5, 6, 7, or 8 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; wherein the coupling of L to BA is selected from the group consisting of: a click chemistry residue, an amide residue, and a residue comprising two cysteine ​​residues of a single BA chemically bonded to L; and k is an integer from 1 to 30.

99. The compound of claim 90 having the structure: in, L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, alkylene, or heteroalkylene, wherein when R 1a When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, alkylene, heteroalkylene, or an amino acid side chain, wherein when R 2 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 3 is H, alkyl, alkylene, or heteroalkylene, wherein when R 3 When it is an alkylene group or a heteroalkylene group, the alkylene group or the heteroalkylene group is further connected to R 1a or R 2 To form the heterocyclic group composed of 4, 5, or 6 atoms; R 4 is H or alkyl; R 5 Yes O, NR 6 , or S; R 6 is H, or alkyl; D* is the residue of a biologically active compound containing a hydroxyl group, an amino group, or a thiol group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

100. The compound according to claim 99, having the structure in, L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, or alkylene, wherein when R 1a When it is an alkylene group, the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, or an amino acid side chain; R 3 is H, alkyl, or alkylene, wherein when R 3 When it is an alkylene group, the alkylene group is further connected to R 1a To form the heterocyclic group composed of 4, 5, or 6 atoms; D* is the residue of a biologically active compound containing a hydroxyl group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

101. The compound of claim 99 having the structure: in, L is a linker; BA is a binding agent; R 1a and R 1b are independently H, alkyl, alkoxy, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, or alkylene, wherein when R 1a When it is an alkylene group, the alkylene group is further connected to R 3 to form a heterocyclic group consisting of 4, 5, or 6 atoms; R 2 is H, or an amino acid side chain; R 3 is H, alkyl, or alkylene, wherein when R 3 When it is an alkylene group, the alkylene group is further connected to R 1a To form the heterocyclic group composed of 4, 5, or 6 atoms; D* is the residue of a biologically active compound containing a hydroxyl group; n is 0, 1, 2, 3, 4, 5, or 6; and k is an integer from 1 to 30.

102. The compound according to any one of claims 90-101, wherein the linker comprises 103. The compound of claim 99, wherein the compound is in, SP 1 and SP 2 , when present, are spacer groups, wherein SP 1 further comprising a moiety reactive with an antibody or antigen-binding fragment thereof; each AA is an amino acid; and P is an integer from 1 to 10.

104. The compound according to claim 103, wherein SP 1 A reactive group is included, wherein the reactive group includes an alkyne.

105. The compound of claim 104, wherein the alkyne is capable of participating in a 1,3-cycloaddition reaction.

106. The compound of claim 105, wherein the alkyne is capable of participating in a 1,3-cycloaddition reaction with the binding agent, wherein the binding agent is an azido-functionalized binding agent.

107. The compound according to claim 103, wherein SP 2 Include 108. The compound according to claim 103, wherein SP 2 Include and R 2 is H or alkyl.

109. The compound of claim 106, wherein the alkyne is capable of participating in a 1,3-cycloaddition reaction with the binding agent, the binding agent is an azido-functionalized binding agent, and SP 2 Include 110. The compound of claim 106, wherein the alkyne is capable of participating in a 1,3-cycloaddition reaction with the binding agent, the binding agent being an azido-functionalized binding agent, 2 Include and R 2 is H or alkyl.

111. The compound of claim 103, wherein the binding agent is an antibody modified with a primary amine compound according to the formula H2N-LL-X, wherein LL is a divalent linker selected from the group consisting of: divalent polyethylene glycol (PEG) group; -(CH2) n -; -(CH2CH2O) n -(CH2) p -; -(CH2) n -N(H)C(O)-(CH2) m -; -(CH2CH2O) n -N(H)C(O)-(CH2CH2O) m -(CH2) p -; -(CH2) n -C(O)N(H)-(CH2) m -; -(CH2CH2O) n -C(O)N(H)-(CH2CH2O) m -(CH2) p -; -(CH2) n -N(H)C(O)-(CH2CH2O) m -(CH2) p -; -(CH2CH2O) n -N(H)C(O)-(CH2) m -; -(CH2) n -C(O)N(H)-(CH2CH2O) m -(CH2) p -;and -(CH2CH2O) n -C(O)N(H)-(CH2) m -, in n is an integer selected from 1 to 12; m is an integer selected from 0 to 12; p is an integer selected from 0 to 2; and X is selected from the group consisting of: -SH, -N3, -C≡CH, -C(O)H, tetrazole, 112. The compound of claim 111, wherein the binding agent is an antibody modified with a primary amine having the structure:

113. The compound of claim 112, wherein the compound is selected from the group consisting of: Where k is 1, 2, 3, or 4.

114. The compound of claim 90, wherein the compound is selected from the group consisting of: and and Wherein z is 1, 2, 3, or 4.

115. An antibody-drug conjugate comprising an antibody, or an antigen-binding fragment thereof, wherein the antibody or antigen-binding fragment thereof is conjugated to a compound according to claim 2 or 39.

116. The antibody-drug conjugate of claim 115, wherein the conjugated compound is selected from the group consisting of:

117. The compound of claim 99, wherein BA is an antibody, or an antigen-binding fragment thereof.

118. The compound of claim 117, wherein BA is a transglutaminase-modified antibody, or an antigen-binding fragment thereof, comprising at least one glutamine residue for conjugation.

119. The compound of claim 117, wherein BA is a transglutaminase-modified antibody, or an antigen-binding fragment thereof, comprising at least two glutamine residues for conjugation.

120. The compound of claim 117, wherein BA is a transglutaminase-modified antibody, or an antigen-binding fragment thereof, comprising at least four glutamine residues for conjugation.

121. The compound of claim 120, wherein BA is a transglutaminase-modified antibody, or an antigen-binding fragment thereof, wherein coupling is performed at two Q295 residues; and k is 2.

122. The compound of claim 120, wherein BA is a transglutaminase-modified antibody, or an antigen-binding fragment thereof, wherein coupling is performed at two Q295 residues and two N297Q residues; and k is 4.

123. A pharmaceutical composition comprising a compound according to any one of the preceding claims, and a pharmaceutically acceptable excipient, carrier, or diluent.

124. A method for treating a disease, disorder or condition associated with glucocorticoid receptor signaling in a subject, comprising administering to the subject an effective amount of a compound or pharmaceutical composition according to any one of the preceding claims.

125. The method of claim 124, wherein the disease, disorder or condition is an inflammatory disease, disorder or condition.

126. The method of claim 124 or 125, wherein side effects associated with administration of the unconjugated steroid payload of the compound are reduced.

127. A method of treating dyslipidemia, a metabolic disease, inflammation, or a neurodegenerative disease in a subject, comprising administering to the subject an effective amount of a compound or pharmaceutical composition according to any one of the preceding claims.

128. A method of treating dyslipidemia in a subject, comprising administering to the subject an effective amount of a compound or pharmaceutical composition according to any one of the preceding claims.

129. A method of treating a metabolic disease in a subject, comprising administering to the subject an effective amount of a compound or pharmaceutical composition according to any one of the preceding claims.

130. A method of treating inflammation in a subject, comprising administering to the subject an effective amount of a compound or pharmaceutical composition according to any one of the preceding claims.

131. A method of treating a neurodegenerative disease in a subject, comprising administering to the subject an effective amount of a compound or pharmaceutical composition according to any one of the preceding claims.

132. A method of preparing an antibody-drug conjugate comprising contacting a binding agent with a compound of claim 39.

133. The compound of claim 2 having the structure: or a pharmaceutically acceptable salt thereof.

134. The compound according to claim 2, having the following structure: or a pharmaceutically acceptable salt thereof.

135. The compound according to claim 2, having the structure: or a pharmaceutically acceptable salt thereof.

136. The compound according to claim 2, having the following structure: or a pharmaceutically acceptable salt thereof.

137. The compound of claim 39 having the structure: or a pharmaceutically acceptable salt thereof.

138. The compound of claim 39 having the structure: or a pharmaceutically acceptable salt thereof.

139. The compound according to claim 39, having the structure: or a pharmaceutically acceptable salt thereof.

140. The compound of claim 39 having the structure: or a pharmaceutically acceptable salt thereof.

141. The compound of claim 99 having the structure:

142. The compound of claim 99 having the structure:

143. The compound of claim 99 having the structure:

144. The compound of claim 99 having the structure:

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