Prodrug kit for multi-flow chemotherapy

Abstract

A prodrug kit for multi-factor dynamic chemotherapy, comprising N different small molecule drug conjugates selected from the Si = Fci-Li-Ct series; wherein i = 1, 2, 3,... 360, N is greater than or equal to 2 and less than or equal to 360, Fc is a part capable of being split by fibroblast activation protein, Li is a connector capable of being split automatically, and Ct is a known chemotherapeutic agent.

Description

Technical Field

[0001] The present invention relates to a prodrug kit for multi - factor dynamic chemotherapy, which comprises N different small - molecule drug conjugates selected from the group consisting of:

[0002] S i = Fc i -L i -Ct i where i = 1, 2, 3, …, 360

[0003] where 2 ≤ N ≤ 360, Fc i is a part cleavable by fibroblast - activating protein, L i is a self - cleaving linker, and Ct i is a known chemotherapeutic drug.

[0004] Cancer remains a major health problem globally. Despite significant research efforts dedicated to understanding cancer biology and designing new therapies, only limited success has been achieved in the treatment of leukemia and non - solid or soft - tissue tumors. According to recent statistics from the International Agency for Research on Cancer (IARC) under the World Health Organization (WHO) or the American Cancer Society (ACS), the incidence, mortality, and economic burden of cancer are increasing at an alarming rate globally. In 2014, the IARC reported that the global war on cancer cannot be won by treatment alone and urged the implementation of preventive strategies to alleviate the impending cancer crisis.

[0005] Most cancer tumors can be surgically removed if diagnosed early. Treatment methods for advanced or inoperable malignancies include:

[0006] - Radiotherapy;

[0007] - Systemic or targeted chemotherapy using cytotoxic drugs, kinase inhibitors, immune checkpoint inhibitors, antibody - drug conjugates (ADCs) or small - molecule drug conjugates (SMDCs); and

[0008] - Immunotherapy, especially chimeric antigen receptor therapy (CAR T).

[0009] Unfortunately, despite an initially favorable response to treatment, the development of resistance to these treatments remains a major cause of cancer recurrence and death. To identify new treatment strategies and improve clinical outcomes, there is an urgent need to better understand the molecular mechanisms underlying cancer progression and acquired resistance. In recent years, many biological mechanisms leading to treatment resistance have been discovered, such as activation of growth factor receptors and their downstream signaling pathways, DNA repair mechanisms, metabolic reprogramming, microRNA expression and metastasis, ATP-binding cassette transporter-mediated drug efflux, and enrichment of cancer stem cell populations. Another important mechanism associated with drug and radiation resistance is the bidirectional communication between cancer cells and their microenvironment (stromal cells, vascular endothelial cells, immune cells), which appears to be mediated by extracellular vesicles and their molecular cargo. More recently, the key role of the gut microbiome in tumor progression and the response of patients to different anticancer drugs has also been recognized. In this context, naturally occurring phytochemicals have regained attention.

[0010] An increasing amount of research effort is dedicated to identifying new biomarkers to predict treatment response and prevent cancer recurrence. Circulating tumor cells, as well as circulating tumor DNA, cancer cell secretomes, tumor-derived extracellular vesicles, and microRNAs (miRNAs) can be easily isolated from the body fluids of patients. Therefore, liquid biopsy is currently regarded as a promising tool for cancer detection and the determination of appropriate treatment regimens.

[0011] Most drugs used in targeted therapies, precision medicine, or personalized cancer therapies, as well as recent immunotherapies, target and modulate specific cancer-related molecules that are overexpressed or underexpressed, such as hormones, enzymes, epitopes, growth factors, kinases, cytokines, chemokines, cell receptors, or adaptor proteins (e.g., Kras, P-glycoprotein, BCR, PI3K, CD11, CD22, CD44, Myc, BRCA2, ALK, IL-10, IL-12, p53, p27, p70, mitogen-activated protein kinases, tyrosine kinase inhibitors, vascular endothelial growth factor, epidermal growth factor). These molecular targets originate from altered or mutated genes (e.g., DNA damage, hypomethylated or hypermethylated genes and their expression products). Targeted molecular entities are part of the highly heterogeneous biochemical environment of cancer. However, despite promising results in in vitro studies and mouse xenograft tumor experiments, most targeted molecular entities have limited clinical translation potential on their own. This paradox is borne out in clinical trials, in which approximately 97% of new candidate drugs fail to bring about substantial improvements.

[0012] In addition, patients with stage III or IV cancer who are treated according to established chemotherapy regimens often develop drug resistance and progress to the metastatic stage involving lymph nodes, liver, lungs, bones, and the brain, ultimately leading to multiple organ failure, vascular damage, triggering proteolytic cascades, and disseminated intravascular coagulation, which are extremely difficult to cure.

[0013] In contrast to the extensive research on the molecular mechanisms of drug resistance, the understanding of how drug resistance arises remains limited. Recent studies have shown that drug resistance may originate from heterogeneous, weakly drug-resistant cell subsets with different sensitivities to chemotherapy drugs. Experimental studies have pointed out that it is not the usually assumed random single (epigenetic) mutation transition or drug-induced reprogramming, but a mixed scenario involving a stepwise multi-factor adaptation through various coordinated genetic and epigenetic changes.

[0014] Nevertheless, most first-line and second-line treatment regimens still rely on one or two chemotherapy drugs (mostly cytotoxic drugs), partly supplemented with adjuvants that can reduce side effects. Given the transient multi-factor adaptation ability of cancer cells, the treatment regimens established clinically based on the long-term repeated use of one or two chemotherapy drugs do not seem sufficient.

[0015] Since the 1980s, by combining potent drugs with different mechanisms of action, the cure rates of the VAMP (vincristine, doxorubicin, methotrexate, prednisone) regimen and the RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) regimen in childhood acute lymphoblastic leukemia (ALL) and diffuse large B-cell lymphoma (DLBCL) have reached over 90% and over 60% respectively. For solid tumors, the cure rate is much lower because solid tumors can protect cancer cells from attacks by the immune system and large exogenous molecules such as antibodies. Prodrugs targeting cancer-associated fibroblasts / fibroblast activation protein (CAF / FAP) with reduced systemic toxicity can overcome the stromal barrier.

[0016] Innovative treatment regimens and FAP (fibroblast activation protein) prodrugs are inspired by and utilize the following:

[0017] (i) A large number of clinically validated, old and newer original cancer drugs;

[0018] (ii) The increasingly common combination therapies;

[0019] (iii) The latest advances in cancer research, such as the following:

[0020] – A.E. Pomeroy, E.V. Schmidt, P.K. Sorger, A.C. Palmer; "Drug Independence and Combination Chemotherapy for Cancer Cure"; Cancer Trends, November 2022, Volume 8, Issue 11; https: / / doi.org / 10.1016 / j.trecan.2022.06.009:

[0021] Conclusion: In this article, we review three historical principles that describe how combinations of independent and effective therapies can address the challenge of tumor heterogeneity and kill more cancer cells in more patients. None of these principles require synergistic drug interactions (i.e., supra-additive activity) to improve treatment outcomes, although their significant clinical benefits are often colloquially referred to as synergistic (i.e., beneficial to patients). Thus, the common view that "we need synergistic drug combinations to overcome drug resistance" is quantitatively incorrect. The multiple meanings of "synergy" have long been a source of confusion in the mechanisms of combination therapies

[38] , and

[0022] have led to the neglect of tumor heterogeneity and drug cross-resistance as key factors in the efficacy of combination therapies.

[0023] – A.O. Pisco, A. Brock, J. Zhou, A. Moor, M. Mojtahedi, D. Jackson, S. Huang; "Non-Darwinian Dynamics in Therapy-Induced Cancer Drug Resistance"; Nature Communications 4, 2467 (2013); https: / / doi.org / 10.1038 / ncomms3467:

[0024] The development of drug resistance is the main cause of cancer treatment failure and is usually explained as the selection of drug-resistant mutant cancer cells. However, the dynamic non-genetic heterogeneity of clonal cell populations continuously generates metastable phenotypic variations (persister cells), some of which represent stem cell-like states that confer drug resistance... We show by quantitative measurement and modeling that the emergence of multidrug resistance protein 1 (MDR1)-positive cells 1 - 2 days after vincristine (VINC) treatment is mainly mediated by cell individual-induced MDR1 expression, rather than by the selection of MDR1-expressing cells.

[0025] –Professor Kornelia Polyak: “However, it seems that most cancer treatment research is based on finding new drug targets, while ignoring the fact that every invented cancer drug selects for drug resistance. We need to face this fact and figure out how to prevent or control treatment resistance.”

[0026] –J.West, L.You, J.Zhang, R.A.Gatenby, J.S.Brown, P.K.Newton, A.R.A.Anderson; "Towards multi-drug adaptive therapy"; Cancer Research 2020, 80:1578-89; doi:10.1158 / 0008-5472.CAN-19-2669.

[0027] –A.H.Briggs et al.; "A value attribution framework for combination therapies"; https: / / assets-dam.takeda.com / raw / upload / v1675187100 / legacy-dotcom / siteassets / en-gb / home / what-we-do / combination-treatments / a-value-attribution-framework-for-combination-therapies-takeda-whitepaper.pdf.

[0028] –https: / / www.fiercepharma.com / pharma / after-ira-victory-senate-doubles-down-more-initiatives-cut-drug-pices.

[0029] –AVA6000 clinical results: https: / / avacta.wistia.com / medias / tc76pkecuy; https: / / avacta.com / first-patient-dosed-in-fifth-cohort-of-ava6000-phase-ia-dose-escalation-study / .

[0030] – A. Zana, A. Galbiati, E. Gilardoni, M. Bocci, J. Millul, T. Sturm, R. Stucchi, A. Elsayed, L. Nadal, M. Cirillo, W. Roll, L. Stegger, I. Asmus, P. Backhaus, M. Schaefers, D. Neri, S. Cazzamalli; "Fibroblast activation protein triggers drug payload release of non-internalized small molecule-drug conjugates in solid tumors"; Clinical Cancer Research CCR-22-1788, October 10, 2022; https: / / doi.org / 10.1158 / 1078-0432.CCR-22-1788.

[0031] – M. Qi, S. Fan, M. Huang, J. Pan, Y. Li, Q. Miao, W. Lyu, X. Li, L. Deng, S. Qiu, T. Liu, W. Deng, X. Chu, C. Jiang, W. He, L. Xia, Y. Yang, J. Hong, Q. Qi, W. Yin, X. Liu, C. Shi, M. Chen, W. Ye, D. Zhang; "Targeting FAPα-expressing hepatic stellate cells overcomes anti-angiogenic resistance in a colorectal cancer liver metastasis model"; Journal of Clinical Investigation 2022;132(19):e157399; doi:10.1172 / JCI157399; https: / / jci.me / 157399 / pdf

[0032] – G. Ye, M. Huang, Y. Li, J. Ouyang, M. Chen, Q. Wen, X. Li, H. Zeng, P. Long, Z. Fan, J. Yin, W. Ye, D. Zhang; "FAPα-activated prodrug Z-GP-DAVLBH inhibits the growth and lung metastasis of osteosarcoma cells by suppressing the AXL pathway"; Acta Pharmaceutica Sinica B 2022;12(3):1288e1304; https: / / doi.org / 10.1016 / j.apsb.2021.08.015

[0033] – X. Xu, R. Kumari, J. Zhou, J. Chen, B. Mao, J. Wang, M. Zheng, X. Tu, X. An, X. Chen, L. Zhang, X. Tian, H. Wang, X. Dong, Z. Bao, S. Guo, X. Ouyang, L. Shang, F. Wang, X. Yan, R. Zhang, R. G. J. Vries, H. Clevers, Q.-X. Li; "A Living Biobank of Patient-Derived Xenografts and Organoid Matched Pairs for Cancer Pharmacology"; *PLoS ONE* 18(1): e0279821; https: / / doi.org / 10.1371 / journal.pone.0279821.

[0034] – Y. Kieffer, H. R. Hocine, G. Gentric, F. Pelon, C. Bernard, B. Bourachot, S. Lameiras, L. Albergante, C. Bonneau, A. Guyard, K. Tarte, A. Zinovyev, S. Baulande, G. Zalcman, A. Vincent-Salomon, F. Mechta-Grigoriou; "Single-Cell Analysis Reveals Fibroblast Clusters Associated with Cancer Immunotherapy Resistance"; *Cancer Discovery* 2020, 10: 1330 - 51; doi:10.1158 / 2159-8290.CD-19-1384.

[0035] – N. Ortiz-Otero, J. R. Marshall, B. Lash, M. R. King; "Chemotherapy Induces Circulating Tumor Cells and Cancer-Associated Fibroblasts to Enter the Bloodstream as a Collective Migration Unit in Patients with Metastatic Cancer"; *BMC Cancer* (2020) 20: 873; https: / / doi.org / 10.1186 / s12885-020-07376-1.

[0036] – J.-W. Seo, K. Fu, S. Correa, M. Eisenstein, E. A. Appel, H. T. Soh; "Real-Time Monitoring of Drug Pharmacokinetics within Tumor Tissues in Living Animals"; *Science Advances* 8, eabk2901 (2022); https: / / www.science.org / doi / epdf / 10.1126 / sciadv.abk2901.

[0037] Cancer treatment and drug therapy generally follow the "magic bullet" and fractionated dosing, i.e., the long-term "maximum tolerated dose" paradigm. However, cancer involves heterogeneous cell populations that adapt metabolically, transcriptionally, epigenetically, and evolutionarily to immune, chemical, or radiation stress over hours, days, weeks, and months. To address the variability of cancer, the present invention includes:

[0038] - Approximately 360 different small molecule drug conjugates (SMDCs), each containing one or more FAP-activatable initiators Fc, self-cleaving linkers L, and a known and proven chemotherapeutic drug Ct;

[0039] - Extracellular prodrug cleavage by fibroblast activation protein (FAP) overexpressed in solid tumors, metastases, and aggregated with circulating tumor cells (CTCs);

[0040] - Pan-cancer therapy, preferably personalized;

[0041] - Simultaneous administration of multiple prodrugs ("pan-therapy"), preferably without cross-resistance;

[0042] - High variability, e.g., selecting 2 prodrugs from 360 provides approximately 129,000 different combinations;

[0043] - Prodrug combinations that change rapidly over time, are non-redundant, non-mutagenic, and preferably rational;

[0044] - Elimination of heterogeneous cancer cell populations;

[0045] - Circumventing tumor adaptation and drug resistance;

[0046] - Collateral damage to cancer-associated fibroblasts (CAFs) and the tumor microenvironment (TME), which enhances the immune system's access to cancer cells;

[0047] - Reduction of systemic toxicity by more than 10-fold;

[0048] - Low-risk / benign clinical trials and facilitation of approval due to low toxicity and use of known chemotherapeutic drug Ct;

[0049] - Affordable prodrug kits;

[0050] - Improved pharmacokinetics / pharmacodynamics (PK / PD) compared to prior art FAP prodrugs.

[0051] Generally, a small prodrug kit containing approximately four CAF / FAP-targeted prodrugs of the present invention should be sufficient to achieve pan-therapy (i.e., kill more than 10 to the 12th power of cancer cells) and incidentally restore the immune response.

[0052] Seo et al. measured the pharmacokinetic parameters of the cancer drug doxorubicin in an in vivo tumor model using a novel sensor:

[0053]

[0054] *AUC 0-t refers to the area under the curve before the drug concentration drops to zero

[0055] Pisco et al., Seo et al., and a large body of scientific literature have shown that:

[0056] - Cancer cells - like most cells - have the ability to adapt and utilize a variety of evolutionary defense mechanisms that enable them to rapidly and flexibly adapt to therapeutic attacks;

[0057] - Drug exposure within tumors is anisotropic, which can prompt cancer cells in low-dose regions to develop drug resistance;

[0058] - The drug clearance rate in the body and within tumors is rapid, thus requiring rapid and efficient drug delivery within the tumor.

[0059] Therefore, in order to overcome refractory cancers, the present invention proposes a multi-pronged, rapidly changing over time treatment regimen that includes two, three, four, five, or more stages, where:

[0060] - The duration of each stage ranges from 48 hours to several weeks;

[0061] - Each stage includes one or more simultaneous administrations of a group of two, three, four, five, or more different tumor-targeted prodrugs; and

[0062] - The group of prodrugs administered in a given stage is different from each group of prodrugs administered in a previous or subsequent stage.

[0063] The proposed treatment regimen has the following advantages:

[0064] - It can achieve high-dose administration of chemotherapeutic drugs to tumors with minimal side effects;

[0065] - Exposes cancer cells to a multitude of different chemotherapeutic drugs in a rapidly changing sequence;

[0066] - Deals with heterogeneous populations of cancer cells;

[0067] - Combats the adaptability and drug resistance of cancer cells;

[0068] - Increases the likelihood of completely eradicating cancer stem cells.

[0069] The treatment regimen outlined above is implemented by using a chemotherapy drug kit that contains N different off-the-shelf small molecule drug conjugates selected from the group consisting of:

[0070] Si = Fc i ―L i ―Ct i where i = 1, 2, 3, …, 360

[0071] - wherein:

[0072] - 2 ≤ N ≤ 360,

[0073] - each Ct i is a residue of a known chemotherapy compound,

[0074] - when i ≠ j, Ct i ≠ Ct j ,

[0075] - each Fc i is a residue of a cleavable moiety of fibroblast activation protein (FAP),

[0076] - each L i is a residue of a self-cleaving linker, and

[0077] - Fc i and Ct i are covalently coupled to L i .

[0078] In a preferred embodiment of the chemotherapy drug kit, each S i is provided in a separate container (such as a medical vial or ampoule).

[0079] According to the present invention, each Ct i is a residue of one of the known chemotherapy drugs shown in Table 1 and Table 2 below. Many of the chemotherapy drugs listed in Table 1 and Table 2 have been used in clinical practice for many years, in some cases even for decades.

[0080] In the chemical structures shown in Table 1 and Table 2, the groups suitable for covalent coupling with the self-cleaving linker L i are marked by dashed circles. Generally, a hydroxyl group (OH - ), a primary amine (NH 2 - ) or a secondary amine (R-NH-R') group is suitable for coupling by being substituted by a hydrogen (H) from the self-cleaving linker L i .

[0081] Table 1: Chemotherapy compounds (Ct i ) that mainly act as inhibitors or regulators

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[0155] Table 2: Chemotherapeutic Compounds with Mainly Cytotoxic Effects (Ct i )

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[0184] The vast majority of the chemotherapeutic compounds listed in Tables 1 and 2 can be readily obtained from commercial suppliers or prepared from commercially available compounds by straightforward derivatization methods. The self-cleaving linker L in the present invention i is also the same (e.g., available from https: / / bezwadabiomedical.com / ), which can be appropriately functionalized and protected to sequentially couple with the hydroxyl or amine group of the fibroblast activation protein (FAP)-cleavable moiety Fc i and the chemotherapeutic compounds in Tables 1 and 2. The strategies and protocols for chemical synthesis and coupling via amide or ether bonds are presented in Examples 1 to 4.

[0185] The present invention has the following advantages:

[0186] - Each Ct i is known and has well-defined pharmacological activities;

[0187] - Each S i is pharmacologically inactive until it is linked to and cleaved by fibroblast activation protein (FAP) mainly expressed by cancer-associated fibroblasts (CAFs) in tumor tissues and metastatic lesions;

[0188] - Each S i is pharmacologically optimized, has good solubility and stability in serum, and can remain in the body for a long time;

[0189] - Each S i is suitable for large-scale synthesis and economical production;

[0190] - The chemotherapeutic drug kit can be produced in an efficient and economical manner;

[0191] - The chemotherapeutic drug kit has a wide range of uses and is convenient for clinical use.

[0192] The small molecule drug conjugate (or prodrug) Si of the present invention comprises a moiety that can be enzymatically cleaved by fibroblast activation protein (FAP). Fibroblast activation protein (FAP) is expressed almost exclusively in the microenvironment (or stroma) of the body's healing wounds and cancer tumors. Many cancer tumors contain a tumor microenvironment (stroma) surrounding cancer cells (neoplastic cells). The tumor stroma contains a variety of non-malignant cell types, which can account for up to 90% of the total tumor mass and plays an important role in providing nutrients for cancer cells and tumor progression and metastasis. Important components of the tumor stroma include the extracellular matrix (ECM), endothelial cells, pericytes, macrophages, immune regulatory cells, and activated fibroblasts, the latter of which are commonly referred to as cancer-associated fibroblasts (CAFs). During tumor progression, cancer-associated fibroblasts (CAFs) change their morphology and biological functions, and these changes are induced by intercellular communication between cancer cells and cancer-associated fibroblasts (CAFs). Cancer-associated fibroblasts (CAFs) create an environment that promotes the growth of cancer cells. The fact shows that treatment methods targeting only cancer cells are not sufficient, and effective treatment methods must also consider the tumor microenvironment, especially cancer-associated fibroblasts (CAFs).

[0193] In more than 90% of human epithelial tumors, cancer-associated fibroblasts (CAFs) overexpress fibroblast activation protein (FAP). Therefore, fibroblast activation protein (FAP) is a promising target for cancer drug therapy. However, the role of fibroblast activation protein (FAP) in the body has not been fully elucidated, and it is known to be a serine protease with unique enzymatic activity, possessing both dipeptidyl peptidase (DPP) and prolyl oligopeptidase (PREP) activities. Therefore, in terms of targeting cancer-associated fibroblasts (CAFs), substrates and inhibitors of dipeptidyl peptidase (DPP), prolyl oligopeptidase (PREP), and fibroblast activation protein (FAP) can be considered as homing ligands. A suitable fibroblast activation protein (FAP) ligand must have high selectivity for related enzymes (such as dipeptidyl peptidase DPPII, DPPIV, DPP8, DPP9, and homologous prolyl oligopeptidase) commonly present in healthy tissues.

[0194] Since 2014 and 2019, small molecule ligands with high affinity and high selectivity for fibroblast activation protein (FAP) have been known (see "Extended Structure-Activity Relationships and Pharmacokinetics of (4-Quinolinoyl)glycyl-2-cyanopyrrolidine Inhibitors of Fibroblast Activation Protein (FAP)" by K. Jensen, L. Heilbo, R. Welker, J.D. Cheng, J. Joossens, P. Coessens, L. Massa, A.-M. Lambrechts, I. De Meester, K. Augustijns, P. Vander Venken, Journal of Medicinal Chemistry, April 10, 2014, Vol. 57, No. 7, pp. 3053-3074, DOI: 10.1021 / jm500031w; "Novel Small Molecule-Derived Highly Selective Substrates of Fibroblast Activation Protein (FAP)" by A. Dedeker, G. Vliegen, D. Van Rompaey, A. Pilla, A. Bracke, L. Verheist, K. Jensen, R. Gais-Friedlander, K. Augustijns, H. De Winter, I. De Meester, A.M. Lambrechts, P. Vander Venken, ACS Medicinal Chemistry Letters, 2019, Vol. 10, No. 8, pp. 1173-1179). These ligands contain a modified glycine-proline unit and a linked quinoline group.

[0195] Regarding circulating tumor cells (CTCs), Laskov et al. stated: "For example, when circulating tumor cells (CTCs) are accompanied by stromal cells, they have a higher survival rate in the bloodstream, and at the metastatic site, stromal cells also have an advantage for the early survival and growth of tumor cells (31). Cancer-associated fibroblasts (CAFs) move in groups with macrophages, immune cells, and platelets, and can support, protect circulating tumor cells (CTCs) and increase their survival rate." (See "Cancer-Associated Fibroblasts and Tumor-Associated Macrophages in Cancer and Cancer Immunotherapy" by H. Laskov, A. Orhan, S. Garg, I. Gorgunur, Frontiers in Oncology, May 2021, Vol. 11, Article 668731; page 5, left column, lines 24-29). Therefore, the prodrugs of the present invention may also be activated by circulating cancer-associated fibroblasts (CAFs), thereby affecting circulating tumor cells (CTCs).

[0196] Regarding drugs specifically targeting cancer-associated fibroblasts (CAFs), Laskov et al. (page 12, left column, paragraph 1) further stated: "Regulation / elimination of α-smooth muscle actin (αSMA)-positive or fibroblast activation protein (FAP)-positive cancer-associated fibroblasts (CAFs) has yielded different results. Currently, targeting cancer-associated fibroblasts (CAFs) or tumor-associated macrophages (TAMs) alone does not seem to be an appropriate approach."

[0197] However, the present invention merely uses fibroblast activation protein (FAP) as a means to activate chemotherapeutic drugs and does not intend to regulate or eliminate cancer-associated fibroblasts (CAFs). Accordingly, the prodrugs of the present invention contain chemotherapeutic compounds designed to act on cancer cells. At the same time, cancer-associated fibroblasts (CAFs) are bystanders and may be collateral damage, especially affected by cytotoxic drugs. In many cases, the collateral damage to cancer-associated fibroblasts (CAFs) may enhance the anti-tumor effect of the prodrugs of the present invention.

[0198] The chemotherapy kit of the present invention provides numerous possibilities for the selection and simultaneous administration of two or more prodrugs. Especially in the case of cancer recurrence, completely different treatment regimens can be flexibly and adaptively adopted.

[0199] In a preferred adaptive mode, the therapy of the present invention is accompanied by frequent quantitative diagnoses, such as liquid biopsies and assessments of tumor size, vascular system, and perfusion based on ultrasound. If the selected combination of prodrugs of the present invention does not produce a quantitative improvement effect within 2-3 weeks, a completely different combination of prodrugs can be adopted.

[0200] As described above, the object of the present invention is to provide a chemotherapy drug kit that can:

[0201] - Achieve simple and cost-effective treatment by exposing solid cancer tumors to a variety of different chemotherapeutic drugs in a rapidly changing time series;

[0202] - Inhibit cancer proliferation;

[0203] - Have negligible adverse effects at high tumor-targeted doses.

[0204] This object is achieved by a chemotherapy drug kit that contains N different small molecule drug conjugates selected from the following group:

[0205] S i =Fc i ―Li―Ct i , where i = 1, 2, 3,..., 360

[0206] Where:

[0207] -2 ≤ N ≤ 360,

[0208] - Each Fci independently has the following structure

[0209]

[0210] Where X = -H or -CH 3 , Y = -H or -F, -R1 is a residue of the first pharmacokinetic modulating moiety, and Z is a moiety having a structure selected from the group consisting of structures (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), (12), (13), (14) and (15), and

[0211]

[0212]

[0213] - each L i is a residue of the self-cleaving linker;

[0214] - Ct i and Fc i are covalently bound to L i ;

[0215] - when i ≠ j, Ct i ≠ Ct j ; and

[0216] - each Ct iThe group consisting of deprotonated residues selected from the following compounds, including: 1,2,3,4-tetrahydrostaurosporine, avasoprimycin hydrochloride (17-Dmag), 2-aminopropionitrile, 4SC202, ABBV-CLS 484, abemaciclib, abexinostat, acalabrutinib, acetylbufalin, aderbasib, afatinib, afuresertib, alectinib, alisertib, alpelisib, alvocidib, AMD3465, anlotinib, apalutamide, AR-42, asciminib, atuveciclib, avapritinib, axitinib, AZD7762, BAY1125976, belinostat, β-hydroxyisovaleric acid, BF211, bicalutamide, binimetinib, bortezomib, bosutinib, brigatinib, bufalin, buparlisib, buthionine sulfoximine, cabozantinib, capivasertib, capmatinib, carfilzomib, CEP 9722, ceralasertib, ceritinib, chidamide, CHR-3996, citarinostat, cobimetinib, CompK, copanlisib, crenolanib, crizotinib, CUDC-101, dabrafenib, daclatasvir, dacomitinib, darolutamide, dasatinib, dasatinib D1, dasatinib D2D2), Dasatinib D3, Dasatinib D4, Decitabine, Defactinib, Degarelix, Diethylstilbestrol, Dinaciclib, Dp44mT, DpC, DUPA, Duvelisib, E7016, Ebvaciclib, Eganelisib, Elimusertib, Emavusertib, Enasidenib, Encorafenib, Enitociclib, Entinostat, Entrectinib, Enzalutamide, Epacadostat, Epigallocatechingallate), Epoxomicin, Erdafitinib, Eribulin, Erlotinib, Everolimus, Fasudil, Fedratinib, Filgotinib, Foslinanib, Fostamatinib, Fruquintinib, Galunisertib, Ganetespib, Gedatolisib, Gefitinib, GFH018, Gilteritinib, Givinostat, Glasdegib, Goserelin, GSK2256098, GSK269962A, GSK690693, GUL, Halofuginone, Hymecromone, Ibrutinib, Icotinib, Idelalisib, Imatinib, Imiquimod, Infigratinib, Iniparib, Ipatasertib, Itacitinib, Ivaltinostat, Ivosidenib, Ixazomib, Kevetrin, Lapatinib, Larotrectinib, Lenalidomide, Leniolisib, Lenvatinib, Leuprolide, Linsitinib, Lonafarnib, Lorlatinib, Losartan, Lucitanib, Luminespib, M1096, Marizomib, ME-344, Merestinib, Metformin, MG132, Midostaurin, Miransertib, Mivavotinib, MK2206, Matrix metalloproteinase 9 inhibitor I (MMP9Inhibitor I), Mobocertinib, Mocetinostat, Motesanib, MRTX1133, Navitoclax, Nazartinib, Nedisertib, Neratinib, Nilotinib, Nilutamide, Nintedanib, Niraparib, NMS-P118, NMS-P515, NSC668394, NSC95397, Numidargistat, NVP 2, Olaparib, Olmutinib, Omipalisib, Oprozomib, Osimertinib, OTS 964, Palbociclib, Pamiparib, Panobinostat, Paricalcitol, Parsaclisib, Pazopanib, Pemetrexed, Pemigatinib, Pevonedistat, Pexidartinib, Pifusertib, Plerixafor, PMPA, Ponatinib, Practinostat, Pralsetinib, Prednisone, Prexasertib, Prinomastat, Propranolol, Quisinostat, Quizartinib, Ralimetinib, Ravoxertinib, Regorafenib, Relugolix, Resminostat, Resveratrol, Retaspimycin, Retinoic acid, Ribociclib, Ricolinostat, Rigosertib, Ripretinib, RO3306, Rocilinostat, Rogaratinib, Romidepsin, Rucaparib, Ruxolitinib, S2, S5, Saridegib, SBI 0654454, SCH772984, Seliciclib, Selitrectinib, Selpercatinib, Selumetinib, SGN 2FF, SGX393, Shikonin, Silibinin, Sitravatinib, Sonidegib, Sorafenib, Sotorasib, Staurosporine, SU11274, Sunitinib, Surufatinib, Tacedinaline, Tadalafil, Talazoparib, Taletrectinib, Tarloxotinib, Taselisib, Tazemetostat, Tefinostat, Temsirolimus, Tetrazole, Tivozanib, Tofacitinib, Tozasertib, Trametinib, Tranilast, Tretinoin, Trichostatin, Tucatinib, Tucidinostat, Tuvusertib, Ubenimex, Umbralisib, Uprosertib, USL311, Vactosertib, Valproic acid, Valsartan, Vandetanib, Veliparib, Vemurafenib, Venetoclax, Verteporfin, Vismodegib, Vorinostat, WRG28, WZ811, Xevinapant, Zandelisib, Zanubrutinib, ZM447439, Abiraterone, Aclarubicin, Adozelesin, Alrestatin, Amanitin, Amrubicin, Anthramycin, Arenastatin, Bizelesin, Bleomycin, Camptothecin, Capecitabine, Carzelesin, CC 1065, Chaconine, Chlorambucil, Cryptophycin 24, Cyclophosphamide, Cytarabine, Dacarbazine, Dactinomycin, Daunorubicin, DAVLBH, Deruxtecan, Dexamethasone, Dichloro acetic acid, Dimethyl-SGD-1882, Docetaxel, Dolastatin 10, Doxorubicin, Duocarmycin A, Duocarmycin B1, Duocarmycin B2, Duocarmycin C1, Duocarmycin C2, Duocarmycin D, Duocarmycin GA, Duocarmycin SASA), Emetine, Epirubicin, Eribulin, Etoposide, Floxuridine, Fludarabine, Fluorouracil, Flutamide, Fulvestrant, Gemcitabine, Idarubicin, Ifosfamide, Irinotecan, L–Asparaginase, Lomustine, Melphalan, Mertansine, Methotrexate, Milataxel, Mitoxantrone, Monomethyl Auristatin E, Maytansine, Maytansinoid, Ozogamicin, Paclitaxel, Pirarubicin, Pixantrone, Podophyllotoxin, Procarbazine, Rapamycin, Rachelmycin, Salinomycin, SB T 1214, Selinexor, SN 38, Solamargine, Solanine, Talirine, Temozolomide, Tesetaxel, SG3199 (Tesirine), Thapsigargin, Tomatine, Topotecan, Tubulysin B, Valrubicin, Vinblastine, Vincristine, Vinorelbine, VIP126, Zorubicin.

[0217] Advantageous embodiments of the prodrug compounds of the present invention have one of the following characteristics, or a combination of two or more of the following characteristics (provided that these combined characteristics are not mutually exclusive or contradictory), and are as follows:

[0218] - Each Cti is selected from the group consisting of the deprotonated residues of the following compounds, including: 1,2,3,4-tetrahydrostaurosporine, alvespimycin hydrochloride (17-Dmag), 2-aminopropionitrile, 4SC202, ABBV-CLS 484, abemaciclib, abexinostat, acalabrutinib, acetylbufalin, aderbasib, afatinib, afuresertib, alectinib, alisertib, alpelisib, alvocidib, AMD3465, anlotinib, apalutamide, AR-42, asciminib, atuveciclib, avapritinib, axitinib, AZD7762, BAY1125976, belinostat, β-hydroxyisovaleric acid, BF211, bicalutamide, binimetinib, bortezomib, bosutinib, brigatinib, bufalin, buparlisib, buthionine sulfoximine, cabozantinib, capivasertib, capmatinib, carfilzomib, CEP 9722, ceralasertib, ceritinib, chidamide, CHR-3996, citarinostat, cobimetinib, CompK, copanlisib, crenolanib, crizotinib, CUDC-101, dabrafenib, daclatasvir, dacomitinib, darolutamide, dasatinib, dasatinib-D1 (DasatinibD1), Dasatinib D2, Dasatinib D3, Dasatinib D4, Decitabine, Defactinib, Degarelix, Diethylstilbestrol, Dinaciclib, Dp44mT, DpC, DUPA, Duvelisib, E7016, Ebvaciclib, Eganelisib, Elimusertib, Emavusertib, Enasidenib, Encorafenib, Enitociclib, Entinostat, Entrectinib, Enzalutamide, Epacadostat, Epigallocatechingallate), Epoxomicin, Erdafitinib, Eribulin, Erlotinib, Everolimus, Fasudil, Fedratinib, Filgotinib, Foslinanib, Fostamatinib, Fruquintinib, Galunisertib, Ganetespib, Gedatolisib, Gefitinib, GFH018, Gilteritinib, Givinostat, Glasdegib, Goserelin, GSK2256098, GSK269962A, GSK690693, GUL, Halofuginone, Hymecromone, Ibrutinib, Icotinib, Idelalisib, Imatinib, Imiquimod, Infigratinib, Iniparib, Ipatasertib, Itacitinib, Ivaltinostat, Ivosidenib, Ixazomib, Kevetrin, Lapatinib, Larotrectinib, Lenalidomide, Leniolisib, Lenvatinib, Leuprolide, Linsitinib, Lonafarnib, Lorlatinib, Losartan, Lucitanib, Luminespib, M1096, Marizomib, ME - 344, Merestinib, Metformin, MG132, Midostaurin, Miransertib, Mivavotinib, MK2206, Matrix Metalloproteinase 9 Inhibitor I (MMP9 Inhibitor I), Mobocertinib, Mocetinostat, Motesanib, MRTX1133, Navitoclax, Nazartinib, Nedisertib, Neratinib, Nilotinib, Nilutamide, Nintedanib, Niraparib, NMS-P118, NMS-P515, NSC668394, NSC95397, Numidargistat, NVP 2, Olaparib, Olmutinib, Omipalisib, Oprozomib, Osimertinib, OTS 964, Palbociclib, Pamiparib, Panobinostat, Paricalcitol, Parsaclisib, Pazopanib, Pemetrexed, Pemigatinib, Pevonedistat, Pexidartinib, Pifusertib, Plerixafor, PMPA, Ponatinib, Practinostat, Pralsetinib, Prednisone, Prexasertib, Prinomastat, Propranolol, Quisinostat, Quizartinib, Ralimetinib, Ravoxertinib, Regorafenib, Relugolix, Resminostat, Resveratrol, Retaspimycin, Retinoic acid, Ribociclib, Ricolinostat, Rigosertib, Ripretinib, RO3306, Rocilinostat, Rogaratinib, Romidepsin, Rucaparib, Ruxolitinib, S2, S5, Saridegib, SBI 0654454, SCH772984, Seliciclib, Selitrectinib, Selpercatinib, Selumetinib, SGN 2FF, SGX393, Shikonin, Silibinin, Sitravatinib, Sonidegib, Sorafenib, Sotorasib, Staurosporine, SU11274, Sunitinib, Surufatinib, Tacedinaline, Tadalafil, Talazoparib, Taletrectinib, Tarloxotinib, Taselisib, Tazemetostat, Tefinostat, Temsirolimus, Tetrazole, Tivozanib, Tofacitinib, Tozasertib, Trametinib, Tranilast, Tretinoin, Trichostatin, Tucatinib, Tucidinostat, Tuvusertib, Ubenimex, Umbralisib, Uprosertib, USL311, Vactosertib, Valproic acid, Valsartan, Vandetanib, Veliparib, Vemurafenib, Venetoclax, Verteporfin, Vismodegib, Vorinostat, WRG28, WZ811, Xevinapant, Zandelisib, Zanubrutinib, ZM447439;

[0219] - Each Cti is selected from the group consisting of the deprotonated residues of the following compounds, including: Abiraterone, Aclarubicin, Adozelesin, Alrestatin, Amanitin, Amrubicin, Anthramycin, Arenastatin, Bizelesin, Bleomycin, Camptothecin, Capecitabine, Carzelesin, CC 1065, Chaconine, Chlorambucil, Cryptophycin 24, Cyclophosphamide, Cytarabine, Dacarbazine, Dactinomycin, Daunorubicin, DAVLBH, Deruxtecan, Dexamethasone, Dichloro acetic acid, Dimethyl-SGD-1882, Docetaxel, Dolastatin 10, Doxorubicin, Duocarmycin A, Duocarmycin B1, Duocarmycin B2, Duocarmycin C1, Duocarmycin C2, Duocarmycin D, Duocarmycin GA, Duocarmycin SASA), Emetine, Epirubicin, Eribulin, Etoposide, Floxuridine, Fludarabine, Fluorouracil, Flutamide, Fulvestrant, Gemcitabine, Idarubicin, Ifosfamide, Irinotecan, L–Asparaginase, Lomustine, Melphalan, Mertansine, Methotrexate, Milataxel, Mitoxantrone, Monomethyl Auristatin E, Maytansine, Maytansinoid, Ozogamicin, Paclitaxel, Pirarubicin, Pixantrone, Podophyllotoxin, Procarbazine, Rapamycin, Rachelmycin, Salinomycin, SB T 1214, Selinexor, SN38, Solamargine, Solanine, Talirine, Temozolomide, Tesetaxel, SG3199 (Tesirine), Thapsigargin, Tomatine, Topotecan, Tubulysin B, Valrubicin, Vinblastine, Vincristine, Vinorelbine, VIP126, Zorubicin;

[0220] -Z and R 1 forms a part, the structure of which is selected from the group consisting of the following structures

[0221]

[0222] - Each Fc i independently of one another contains a moiety selected from the group consisting of

[0223]

[0224] wherein the pyrrolidine ring is oriented towards the self-cleavable linker L, Y = -H or -F, and X = -H or -CH 3 ;

[0225] - Each Fc i independently of one another contains a moiety selected from the group consisting of

[0226]

[0227]

[0228] wherein the pyrrolidine ring is oriented towards the self-cleavable linker L;

[0229] - Each Fc i independently of one another has the (following) structure

[0230]

[0231] - Each Fc i independently of one another has the (following) structure

[0232]

[0233] - Each Fc i independently of one another has the (following) structure

[0234]

[0235] - Each Fc i independently of one another has the (following) structure

[0236]

[0237] - Each Fc i independently of one another has the (following) structure

[0238]

[0239] - Each linker L i independently of one another contains a moiety having the following structure

[0240]

[0241] wherein

[0242] - the terminal amine is covalently bound to the Fc i ; and

[0243] -r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10

[0244] - Each L i independently of one another comprises a moiety having the following structure

[0245]

[0246] wherein the terminal amine is covalently linked to Fc i covalently;

[0247] - Each L i independently of one another comprises a moiety having the following structure

[0248]

[0249] - wherein the terminal amine is covalently bound to Fc, and B i covalently, and B i is independently of one another selected from the group consisting of moieties comprising the following

[0250]

[0251] - Each Li, independently of one another, comprises a moiety having a structure selected from the group consisting of the following structures.

[0252]

[0253] wherein the terminal amine is covalently linked to Fc i covalently;

[0254] - Each L i independently of one another comprises a moiety having the following structure

[0255]

[0256] wherein the terminal amine is covalently linked to Fc i covalently;

[0257] - Each L i independently of one another comprises a moiety having the following structure

[0258]

[0259] wherein the terminal amine is covalently linked to Fc i covalently;

[0260] - Each linker L i independently of one another comprises a second pharmacokinetic modulating moiety R 2 ;

[0261] - Each linker L iEach is independently a linker designed to initiate self-cleavage through cyclization;

[0262] - Each linker L i Each is independently a linker designed to initiate self-cleavage through 1,4-elimination;

[0263] - Each linker L i Each is independently a linker designed to initiate self-cleavage through 1,6-elimination;

[0264] - Each linker L i Each is independently a linker designed to initiate self-cleavage through 1,8-elimination;

[0265] - Each linker L i Each independently contains an amino group covalently bound to Fc i ;

[0266] - Each linker L i Each independently has a structure selected from the group consisting of structures (a), (b), (c), (d), (e), (f), (g), (h), (i), (j), (k), (l), (m), (n) and (o)

[0267]

[0268]

[0269] Where:

[0270] - The terminal amine is covalently bound to Fc i ;

[0271] - r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0272] -- A - is absent, or is selected from the group consisting of -O-, -NH-, -CH(OH)-, -CO-, -N(CH 3 )-, -S- and -SH-;

[0273] -- E - is selected from the group consisting of -CH 2 -, -O-, -NH-, -N(CH 3 )-, -S- and -SH 2 -;

[0274] - p = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0275] -q = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and q + s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0276] --R 2 is -H, -CH 3 or is a second pharmacokinetic modulating moiety.

[0277] -Each linker L i independently of one another has the following structure

[0278]

[0279] wherein

[0280] L 1 is selected from the group consisting of structures (a), (b), (c), (d), (e), (f), (g), (h), (i), (j), (k), (l), (m), (n) and (o)

[0281]

[0282]

[0283] wherein:

[0284] -The terminal amine is covalently bound to Fci;

[0285] -r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0286] --A - is absent, or is selected from the group consisting of -O-, -NH-, -CH(OH)-, -CO-, -N(CH 3 )-, -S- and -SH 2 -;

[0287] --E - is selected from the group consisting of -CH 2 -, -O-, -NH-, -N(CH 3 )-, -S- and -SH 2 -;

[0288] -p = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0289] -q = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and q + s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0290] --R2 is -H, -CH 3 or is a second pharmacokinetic modulating moiety; and

[0291] L 2 is selected from the group consisting of structures (a'), (b'), (c'), (d'), (e'), (f'), (g'), (h'), (i'), (j'), (k'), (l'), (m'), (n') and (o')

[0292]

[0293]

[0294] wherein:

[0295] - If L 1 is equivalent to one of structures (a)-(m), then L 2 is equivalent to (n') or (o'); and if L 1 is equivalent to (n) or (o), then L 2 is equivalent to one of structures (a')-(m');

[0296] -- A - is absent, or is selected from the group consisting of -O-, -NH-, -CH(OH)-, -CO-, -N(CH 3 )-, -S- and -SH 2 -;

[0297] -- E - is selected from the group consisting of -CH 2 -, -O-, -NH-, -N(CH 3 )-, -S- and -SH 2 -;

[0298] - t = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0299] - u = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and v = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and u + v = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; and

[0300] -- R 2 - is -H-, -CH 3 - or is a second pharmacokinetic modulating moiety;

[0301] - Each L i independently of one another has this structure

[0302] wherein

[0303] P 1 comprises an amine group covalently bound to Fc i and P 1 is selected from the group consisting of structures

[0304] and the group P j (where 2 ≤ j ≤ h and 2 ≤ h ≤ 10) are each independently selected from the group consisting of the following structures

[0305]

[0306] and, when h < j ≤ 10, Pj is absent;

[0307] - Each L i is mutually independent and has the following structure

[0308] where

[0309] P 1 is selected from the group including the following structures

[0310]

[0311] Fc i and P 1 forms a moiety having a structure selected from the following group

[0312] and

[0313] the group P j (2 ≤ j ≤ h and 2 ≤ h ≤ 10) are each independently selected from the following group

[0314]

[0315]

[0316] and, when h < j ≤ 10, Pj is absent;

[0317] - Each L i is mutually independent and has the following structure

[0318] where

[0319] the amino group is covalently bound to Fc i r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, and the moiety Q having 1 ≤ j ≤ h and 1 ≤ h ≤ 10 j is each independently selected from the following group

[0320]

[0321] And when h < j ≤ 10, Q j is missing;

[0322] - Each L i independently of one another has the following structure

[0323] where p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0324] - Each L i independently of one another has the following structure

[0325] where p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0326] - Each L i independently of one another has the following structure

[0327] where p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0328] - Each L i independently of one another has the following structure

[0329] where, -R 2 is a residue of the second pharmacokinetic modulating moiety and p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0330] - Each L i independently of one another has the following structure

[0331] where, -R 2 is a residue of the second pharmacokinetic modulating moiety and p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0332] - Each L i independently of one another has the following structure

[0333] where, -R 2 is a residue of the second pharmacokinetic modulating moiety and p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0334] - Each L iEach independently has a structure selected from the group consisting of: (a"), (b"), (c"), (d"), (e"), (f"), (g"), (h"), (i"), (j"), (k"), (l"), (m"), (n"), (o"), (p"), (q"), (r") and (s")

[0335]

[0336]

[0337] wherein, -R 2 is -H, -CH 3 or a residue of a second pharmacokinetic modulating moiety, and NU - is a nucleophile selected from O, nitrogen NH or S;

[0338] - Each L i independently has a structure selected from the group consisting of: (a"), (b"), (c"), (d"), (e"), (f"), (g"), (h"), (i"), (j"), (k"), (l"), (m"), (n"), (o"), (p"), (q"), (r"), (s"), and Fc i is covalently bonded to the amino group of L i ;

[0339] - Each L i has structure (a");

[0340] - Each L i has structure (b");

[0341] - Each L i has structure (c");

[0342] - Each L i has structure (d");

[0343] - Each L i has structure (e");

[0344] - Each L i has structure (f");

[0345] - Each L i has structure (g");

[0346] - Each L i has structure (h");

[0347] - Each L i has structure (i");

[0348] - Each Li has structure (j");

[0349] - Each L i has structure (k");

[0350] - Each L i has structure (l");

[0351] - Each L i has structure (m"), where NU- represents a nucleophile selected from O, NH, and S;

[0352] - Each L i has structure (n");

[0353] - Each L i has structure (o");

[0354] - Each L i has structure (p");

[0355] - Each L i has structure (q");

[0356] - Each L i has structure (r");

[0357] - Each L i has structure (s");

[0358] -

[0359] -

[0360] -

[0361] -

[0362] -

[0363] -

[0364] -

[0365] -

[0366] -

[0367] -

[0368] -

[0369] -

[0370] -

[0371] -

[0372] -

[0373] -

[0374] -

[0375] -

[0376] -

[0377] -

[0378] -

[0379] -

[0380] -

[0381] -

[0382] -

[0383] -

[0384] -

[0385] -

[0386] -

[0387] -

[0388] - Each prodrug S i Independently of one another has a structure of type (x) or (y) as follows

[0389]

[0390] wherein M 1 = -O-, -NH-, -N(CH 3 )-, or -S-, M 2 = -CH 2 -,-O- or -NH-, r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0391] - Each prodrug S i independently of one another has a structure of type (x) as follows

[0392]

[0393] where M 1 = -O-, -NH-, -N(CH 3 )-, or -S-, M 2 = -CH 2 -,-O- or -NH- and r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; – where k = 1, 2, 3, …, 999 or 1000;

[0394] – where k = 1, 2, 3, …, 19 or 20;

[0395] –

[0396] –

[0397] -R 1 is a residue as follows, a peptide residue containing 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 amino acids, these amino acids being independently selected from the group consisting of alanine (Ala), arginine (Arg), asparagine (Asn), aspartic acid (Asp), cysteine (Cys), glutamine (Gln), glutamic acid (Glu), glycine (Gly), histidine (His), isoleucine (Ile), leucine (Leu), lysine (Lys), methionine (Met), phenylalanine (Phe), proline (Pro), serine (Ser), threonine (Thr), tryptophan (Trp), tyrosine (Tyr), valine (Val), pyrrolysine (Pyl), selenocysteine (Sec), γ-aminobutyric acid (GABA or γ-aminobutyric acid), homoserine, levodopa (DOPA or 3,4-dihydroxyphenylalanine), citrulline, β-alanine and thyroxine;

[0398] -R 1 is a residue of a lactide oligomer containing 4, 5, …, 39 or 40 monomer units;

[0399] -R 1 is a residue of a lactide-glycolide copolymer oligomer containing 4, 5, …, 39 or 40 monomer units;

[0400] -R 1is an acrylate oligomer residue containing 4, 5, …, 39 or 40 monomer units;

[0401] -R 1 is a methacrylate oligomer residue containing 4, 5, …, 39 or 40 monomer units;

[0402] – where m = 1, 2, 3, …, 999 or 1000;

[0403] – where m = 1, 2, 3, …, 19 or 20;

[0404] –

[0405] –

[0406] –R 2 is a residue of a peptide comprising 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 amino acids independently selected from the group consisting of alanine (Ala), arginine (Arg), asparagine (Asn), aspartic acid (Asp), cysteine (Cys), glutamine (Gln), glutamic acid (Glu), glycine (Gly), histidine (His), isoleucine (Ile), leucine (Leu), lysine (Lys), methionine (Met), phenylalanine (Phe), proline (Pro), serine (Ser), threonine (Thr), tryptophan (Trp), tyrosine (Tyr), valine (Val), pyrrolysine (Pyl), selenocysteine (Sec), γ-aminobutyric acid (GABA or γ-aminobutyric acid), homoserine, levodopa (DOPA or 3,4-dihydroxyphenylalanine), citrulline, β-alanine, and thyroxine;

[0407] -R 2 is a residue of a lactide oligomer containing 4, 5, ……, 39 or 40 monomer units;

[0408] -R 2 is a residue of a lactide-co-glycolide oligomer containing 4, 5, ……, 39 or 40 monomer units;

[0409] -R 2 is a residue of an acrylate oligomer containing 4, 5, ……, 39 or 40 monomer units;

[0410] -R 2is a residue of a methacrylate oligomer comprising 4, 5, ……, 39 or 40 monomer units.

[0411] The second embodiment of the present invention relates to a prodrug having the following structure:

[0412] S = Fc-L–Ct

[0413] wherein:

[0414] —Fc has the following structure

[0415]

[0416] wherein X is -H or -CH 3 , Y is -H or -F, -R 1 is a residue of a first pharmacokinetic modulating moiety, and Z is a moiety whose structure is selected from the group consisting of structures (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), (12), (13), (14) and (15), wherein

[0417]

[0418]

[0419] —L is a residue of a self-cleavable linker;

[0420] —Ct and Fc are covalently bound to L; and

[0421] —Ct is equivalent to a protonated residue and is selected from the following group: 1,2,3,4-tetrahydrostaurosporine, alvespimycin hydrochloride (17-Dmag), 2-aminopropionitrile, 4SC202, ABBV-CLS 484, abemaciclib, abexinostat, acalabrutinib, acetylbufalin, aderbasib, afatinib, afuresertib, alectinib, alisertib, alpelisib, alvocidib, AMD3465, anlotinib, apalutamide, AR-42, asciminib, atuveciclib, avapritinib, axitinib, AZD7762, BAY1125976, belinostat, β-hydroxyisovaleric acid, BF211, bicalutamide, binimetinib, bortezomib, bosutinib, brigatinib, bufalin, buparlisib, buthionine sulfoximine, cabozantinib, capivasertib, capmatinib, carfilzomib, CEP 9722, ceralasertib, ceritinib, chidamide, CHR-3996, citarinostat, cobimetinib, CompK, copanlisib, crenolanib, crizotinib, CUDC-101, dabrafenib, daclatasvir, dacomitinib, darolutamide, dasatinib, dasatinib-D1, dasatinib-D2D2), Dasatinib D3, Dasatinib D4, Decitabine, Defactinib, Degarelix, Diethylstilbestrol, Dinaciclib, Dp44mT, DpC, DUPA, Duvelisib, E7016, Ebvaciclib, Eganelisib, Elimusertib, Emavusertib, Enasidenib, Encorafenib, Enitociclib, Entinostat, Entrectinib, Enzalutamide, Epacadostat, Epigallocatechingallate), Epoxomicin, Erdafitinib, Eribulin, Erlotinib, Everolimus, Fasudil, Fedratinib, Filgotinib, Foslinanib, Fostamatinib, Fruquintinib, Galunisertib, Ganetespib, Gedatolisib, Gefitinib, GFH018, Gilteritinib, Givinostat, Glasdegib, Goserelin, GSK2256098, GSK269962A, GSK690693, GUL, Halofuginone, Hymecromone, Ibrutinib, Icotinib, Idelalisib, Imatinib, Imiquimod, Infigratinib, Iniparib, Ipatasertib, Itacitinib, Ivaltinostat, Ivosidenib, Ixazomib, Kevetrin, Lapatinib, Larotrectinib, Lenalidomide, Leniolisib, Lenvatinib, Leuprolide, Linsitinib, Lonafarnib, Lorlatinib, Losartan, Lucitanib, Luminespib, M1096, Marizomib, ME - 344, Merestinib, Metformin, MG132, Midostaurin, Miransertib, Mivavotinib, MK2206, Matrix metalloproteinase 9 inhibitor I (MMP9Inhibitor I), Mobocertinib, Mocetinostat, Motesanib, MRTX1133, Navitoclax, Nazartinib, Nedisertib, Neratinib, Nilotinib, Nilutamide, Nintedanib, Niraparib, NMS-P118, NMS-P515, NSC668394, NSC95397, Numidargistat, NVP 2, Olaparib, Olmutinib, Omipalisib, Oprozomib, Osimertinib, OTS 964, Palbociclib, Pamiparib, Panobinostat, Paricalcitol, Parsaclisib, Pazopanib, Pemetrexed, Pemigatinib, Pevonedistat, Pexidartinib, Pifusertib, Plerixafor, PMPA, Ponatinib, Practinostat, Pralsetinib, Prednisone, Prexasertib, Prinomastat, Propranolol, Quisinostat, Quizartinib, Ralimetinib, Ravoxertinib, Regorafenib, Relugolix, Resminostat, Resveratrol, Retaspimycin, Retinoic acid, Ribociclib, Ricolinostat, Rigosertib, Ripretinib, RO3306, Rocilinostat, Rogaratinib, Romidepsin, Rucaparib, Ruxolitinib, S2, S5, Saridegib, SBI 0654454, SCH772984, Seliciclib, Selitrectinib, Selpercatinib, Selumetinib, SGN 2FF, SGX393, Shikonin, Silibinin, Sitravatinib, Sonidegib, Sorafenib, Sotorasib, Staurosporine, SU11274, Sunitinib, Surufatinib, Tacedinaline, Tadalafil, Talazoparib, Taletrectinib, Tarloxotinib, Taselisib, Tazemetostat, Tefinostat, Temsirolimus, Tetrazole, Tivozanib, Tofacitinib, Tozasertib, Trametinib, Tranilast, Tretinoin, Trichostatin, Tucatinib, Tucidinostat, Tuvusertib, Ubenimex, Umbralisib, Uprosertib, USL311, Vactosertib, Valproic acid, Valsartan, Vandetanib, Veliparib, Vemurafenib, Venetoclax, Verteporfin, Vismodegib, Vorinostat, WRG28, WZ811, Xevinapant, Zandelisib, Zanubrutinib, ZM447439, Abiraterone, Aclarubicin, Adozelesin, Alrestatin, Amanitin, Amrubicin, Anthramycin, Arenastatin, Bizelesin, Bleomycin, Camptothecin, Capecitabine, Carzelesin, CC 1065, Chaconine, Chlorambucil, Cryptophycin 24, Cyclophosphamide, Cytarabine, Dacarbazine, Dactinomycin, Daunorubicin, DAVLBH, Deruxtecan, Dexamethasone, Dichloro acetic acid, Dimethyl-SGD-1882, Docetaxel, Dolastatin 10, Doxorubicin, Duocarmycin A, Duocarmycin B1, Duocarmycin B2, Duocarmycin C1, Duocarmycin C2, Duocarmycin D, Duocarmycin GA, Duocarmycin SASA), Emetine, Epirubicin, Eribulin, Etoposide, Floxuridine, Fludarabine, Fluorouracil, Flutamide, Fulvestrant, Gemcitabine, Idarubicin, Ifosfamide, Irinotecan, L–Asparaginase, Lomustine, Melphalan, Mertansine, Methotrexate, Milataxel, Mitoxantrone, Monomethyl Auristatin E, Maytansine, Maytansinoid, Ozogamicin, Paclitaxel, Pirarubicin, Pixantrone, Podophyllotoxin, Procarbazine, Rapamycin, Rachelmycin, Salinomycin, SB T 1214, Selinexor, SN 38, Solamargine, Solanine, Talirine, Temozolomide, Tesetaxel, SG3199 (Tesirine), Thapsigargin, Tomatine, Topotecan, Tubulysin B, Valrubicin, Vinblastine, Vincristine, Vinorelbine, VIP126, Zorubicin.

[0422] Advantageous embodiments of the prodrug S = Fc-L-Ct of the present invention have one of the following characteristics or a combination of two or more of the following characteristics, provided that the characteristics of these combinations are not mutually exclusive or contradictory, and depending on the following circumstances:

[0423] —Ct is a group of Dinaciclib;

[0424] —Ct is a group of NVP-2;

[0425] —Ct is a group of Erlotinib;

[0426] —Ct is a group of Imatinib;

[0427] —Ct is a group of Sorafenib;

[0428] —Ct is a group of Bufalin;

[0429] —Ct is a group of Acetylbufalin;

[0430] —Z and R 1 form a part having a structure selected from the following group

[0431]

[0432] -Fc includes a part selected from the group containing the part

[0433]

[0434]

[0435] wherein the pyrrolidine ring faces the self-cleavable linker L, Y is -H or -F, and X is -H or -CH 3 ;

[0436] -Fc includes a part selected from the following group

[0437]

[0438] wherein the orientation of the pyrrolidine ring is towards the self-cleavable linker L;

[0439] -Fc has the following structure

[0440]

[0441] -Fc has the following structure

[0442]

[0443] -Fc has the following structure

[0444]

[0445] -Fc has the following structure

[0446]

[0447] -Fc has the following structure

[0448]

[0449] -L contains a moiety having the following structure

[0450]

[0451] wherein

[0452] - the terminal amine is covalently bound to Fc; and

[0453] - r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0454] -L contains a moiety having the following structure

[0455]

[0456] wherein the terminal amine is covalently bound to Fc;

[0457] -L contains a moiety having the following structure

[0458]

[0459] wherein the terminal amine is covalently bound to Fc, and B1 is selected from the group consisting of the following moieties

[0460]

[0461] -L contains a moiety having a structure selected from the following group

[0462]

[0463]

[0464] wherein the terminal amine is covalently bound to Fc;

[0465] -L contains a moiety having the following structure

[0466]

[0467] wherein the terminal amine is covalently bound to Fc;

[0468] -L contains a moiety having the following structure

[0469]

[0470] wherein the terminal amine is covalently bound to Fc;

[0471] - The linker L contains another pharmacokinetic moiety R 2 ;

[0472] - The linker L is designed to trigger self-cleavage through a cyclization reaction;

[0473] - The linker L is designed to trigger self-cleavage through a 1,4-elimination reaction;

[0474] - The linker L is designed to trigger self-cleavage through a 1,6-elimination reaction;

[0475] - The linker L is designed to trigger self-cleavage through a 1,8-elimination reaction;

[0476] - The linker L contains an amine group covalently bound to Fc;

[0477] - The structure of the linker L is selected from the group consisting of structures (a), (b), (c), (d), (e), (f), (g), (h), (i), (j), (k), (l), (m), (n), and (o),

[0478] wherein

[0479]

[0480]

[0481] wherein

[0482] - The terminal amine is covalently bound to Fc;

[0483] - r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10;

[0484] -- A - is absent or selected from the group consisting of - O -, - NH -, - CH(OH) -, - CO -, - N(CH 3 ) -, - S -, and - SH 2 -;

[0485] -- E - is selected from the group consisting of - CH 2 -, - O -, - NH -, - N(CH 3 ) -, - S -, and - SH 2 -;

[0486] - p = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10;

[0487] -q = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and q + s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0488] --R 2 is -H, -CH 3 or a second pharmacokinetic modulating group;

[0489] - The linker L has the following structure

[0490]

[0491] wherein

[0492] L 1 is selected from the group consisting of structures (a), (b), (c), (d), (e), (f), (g), (h), (i), (j), (k), (l), (m), (n) and (o), wherein

[0493]

[0494]

[0495] wherein

[0496] - The terminal amine is covalently bound to Fc;

[0497] - r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0498] --A - is absent, or is selected from the group consisting of -O-, -NH-, -CH(OH)-, -CO-, -N(CH 3 )-, -S- and -SH 2 -;

[0499] --E - is selected from the group consisting of -CH 2 -, -O-, -NH-, -N(CH 3 )-, -S- and -SH 2 -;

[0500] - p = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0501] - q = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and q + s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0502] --R 2 is -H, -CH3 or a second pharmacokinetic modulating group; and

[0503] L 2 is selected from the group consisting of structures (a'), (b'), (c'), (d'), (e'), (f'), (g'), (h'), (i'), (j'), (k'), (l'), (m'), (n') and (o'), wherein

[0504]

[0505]

[0506] wherein

[0507] - if L 1 is equal to any one of structures (a) to (m), then L 2 is equal to (n') or (o'); if L 1 is equal to (n) or (o), then L 2 is equal to any one of structures (a') to (m');

[0508] --A - is absent, or is selected from the group consisting of -O-, -NH-, -CH(OH)-, -CO-, -N(CH 3 )-, -S- and -SH 2 -;

[0509] --E - is selected from the group consisting of -CH 2 -, -O-, -NH-, -N(CH 3 )-, -S- and -SH 2 -;

[0510] - t = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0511] - u = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and v = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and u + v = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; and

[0512] --R 2 is -H, -CH 3 or a second pharmacokinetic modulating group;

[0513] - The linker L has the following structure

[0514] wherein

[0515] P 1 comprises an amine group covalently bound to Fc, P 1Selected from the following group including

[0516] and

[0517] When 2 ≤ j ≤ h and 2 ≤ h ≤ 10, the group P j Is independently selected from the group consisting of the following groups

[0518]

[0519] And, when h < j ≤ 10, P j Does not exist;

[0520] -L has the following structure

[0521] Wherein

[0522] P 1 Is selected from the group consisting of the following structures

[0523]

[0524] Fc and P 1 Form a structure selected from the group consisting of the following groups

[0525] And

[0526] When 2 ≤ j ≤ h and 2 ≤ h ≤ 10, the group P j Is independently selected from the group consisting of the following groups

[0527]

[0528]

[0529] And, when h < j ≤ 10, P j Does not exist;

[0530] -The linker L has the following structure

[0531] Wherein

[0532] The amino group is covalently bonded to Fc, r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and when 1 ≤ j ≤ h and 1 ≤ h ≤ 10, the group Q j Is independently selected from the group consisting of the following groups

[0533]

[0534] And, when h < j ≤ 10, Q j Does not exist;

[0535] - The linker L has the following structure

[0536] where p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0537] - The linker L has the following structure

[0538] where p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0539] - The linker L has the following structure

[0540] where p = 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0541] - The linker L has the following structure

[0542] where -R 2 is the residue of a second pharmacokinetic modulating group, and p = 1, 2,

[0543] 3, 4, 5, 6, 7, 8, 9 or 10;

[0544] - The linker L has the following structure

[0545] where -R 2 is the residue of a second pharmacokinetic modulating group, and p = 1, 2,

[0546] 3, 4, 5, 6, 7, 8, 9 or 10;

[0547] - The linker L has the following structure

[0548] where -R 2 is the residue of a second pharmacokinetic modulating group, and p = 1, 2,

[0549] 3, 4, 5, 6, 7, 8, 9 or 10;

[0550] - The structure of the linker L is selected from the group consisting of (a"), (b"), (c"), (d"), (e"), (f"), (g"), (h"), (i"), (j"), (k"), (l"), (m"), (n"), (o"), (p"), (q"), (r") and (s"), where

[0551]

[0552]

[0553] wherein, -R 2 is -H, -CH 3 or a residue of a second pharmacokinetic modulating group, and NU - is a nucleophile selected from O, NH or S;

[0554] - The linker L has a structure selected from the group consisting of (a"), (b"), (c"), (d"), (e"), (f"), (g"), (h"), (i"), (j"), (k"), (l"), (m"), (n"), (o"), (p"), (q"), (r"), (s"), and Fc is covalently bound to the amine group of L;

[0555] - The linker L has the structure (a");

[0556] - The linker L has the structure (b");

[0557] - The linker L has the structure (c");

[0558] - The linker L has the structure (d");

[0559] - The linker L has the structure (e");

[0560] - The linker L has the structure (f");

[0561] - The linker L has the structure (g");

[0562] - The linker L has the structure (h");

[0563] - The linker L has the structure (i");

[0564] - The linker L has the structure (j");

[0565] - The linker L has the structure (k");

[0566] - The linker L has the structure (l");

[0567] - The linker L has the structure (m"), where NU - represents a nucleophile selected from O, NH and S;

[0568] - The linker L has the structure (n");

[0569] - The linker L has the structure (o");

[0570] - The linker L has the structure (p");

[0571] - The linker L has the structure (q");

[0572] - The linker L has the structure (r");

[0573] - The connecting body L has a structure (s").

[0574] -

[0575] -

[0576] -

[0577] -

[0578] -

[0579] -

[0580] -

[0581] -

[0582] -

[0583] -

[0584] -

[0585] -

[0586] -

[0587] -

[0588] -

[0589] -

[0590] -

[0591] -

[0592] -

[0593] -

[0594] -

[0595] -

[0596] -

[0597] -

[0598] -

[0599] -

[0600] -

[0601] -

[0602] -

[0603] -

[0604] - The prodrug S has a structure of type (x) or (y), where

[0605]

[0606] where M 1 = -O-, -NH-, -N(CH 3 )-, or -S-, M 2 = -CH 2 -,-O- or -NH-, r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0607] The prodrug S has a structure of type (x), where

[0608]

[0609] where M 1 = -O-, -NH-, -N(CH 3 )-, or -S-, M 2 = -CH 2 -,-O- or -NH- and r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0610] – where k = 1, 2, 3, …, 999 or 1000;

[0611] – where k = 1, 2, 3, …, 19 or 20;

[0612] –

[0613] –

[0614] –R 1is a residue of a peptide comprising 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 amino acids independently selected from the group consisting of alanine (Ala), arginine (Arg), asparagine (Asn), aspartic acid (Asp), cysteine (Cys), glutamine (Gln), glutamic acid (Glu), glycine (Gly), histidine (His), isoleucine (Ile), leucine (Leu), lysine (Lys), methionine (Met), phenylalanine (Phe), proline (Pro), serine (Ser), threonine (Thr), tryptophan (Trp), tyrosine (Tyr), valine (Val), pyrrolysine (Pyl), selenocysteine (Sec), gamma-aminobutyric acid (GABA or homoserine, dopa (DOPA or 3,4-dihydroxyphenylalanine), citrulline, beta-alanine (beta Alanine) and thyroxine;

[0615] –R 1 is a residue of a lactide oligomer comprising 4, 5, …, 39 or 40 monomer units;

[0616] –R 1 is a residue of a lactide-glycolide copolymer oligomer consisting of 4, 5, …, 39 or 40 monomer units;

[0617] –R 1 is a residue of an acrylate oligomer comprising 4, 5, …, 39 or 40 monomer units;

[0618] –R 1 is a residue of a methacrylate oligomer containing 4, 5, …, 39 or 40 monomer units;

[0619] – where m = 1, 2, 3, …, 999 or 1000;

[0620] – where m = 1, 2, 3, …, 19 or 20;

[0621] –

[0622] –

[0623] –R 2is a residue of a peptide that comprises 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 amino acids, which are independently selected from the group consisting of the following amino acids: alanine (Ala), arginine (Arg), asparagine (Asn), aspartic acid (Asp), cysteine (Cys), glutamine (Gln), glutamic acid (Glu), glycine (Gly), histidine (His), isoleucine (Ile), leucine (Leu), lysine (Lys), methionine (Met), phenylalanine (Phe), proline (Pro), serine (Ser), threonine (Thr), tryptophan (Trp), tyrosine (Tyr), valine (Val), pyrrolysine (Pyl), selenocysteine (Sec), γ-aminobutyric acid (GABA or homoserine, dopa (DOPA or 3,4-dihydroxyphenylalanine), citrulline, β-alanine, and thyroxine;

[0624] –R 2 is a residue of a lactide oligomer that comprises 4, 5, …, 39 or 40 monomer units;

[0625] –R 2 is a residue of a lactide-glycolide copolymer oligomer that consists of 4, 5, …, 39 or 40 monomer units;

[0626] –R 2 is a residue of an acrylate oligomer that comprises 4, 5, …, 39 or 40 monomer units;

[0627] –R 2 is a residue of a methacrylate oligomer that contains 4, 5, …, 39 or 40 monomer units.

[0628] The present invention also provides multivalent prodrugs containing two or more FAP-activatable initiators. The multivalent prodrugs have higher uptake in tumors and can release the corresponding parent drugs more effectively. Compared with the monovalent prodrugs containing a single FAP-activatable initiator, the multivalent prodrugs have a higher docking and activation probability, which, in physical terms, means a larger effective cross-section. Better tumor uptake and parent drug release help reduce the dosage and further alleviate adverse side effects.

[0629] In the prodrugs or antibody-drug conjugates (SMDCs) of the present invention, each of one or more FAP-activatable initiators or trigger groups is covalently linked to a linear or branched self-cleavable linker, which in turn is covalently linked to a group or residue of a chemotherapeutic compound (parent drug). The prodrugs or SMDCs of the present invention are designed to be activated extracellularly by FAP, which is overexpressed in various solid tumors. Catalytic cleavage of the initiator or trigger group from the linear or branched self-cleavable linker by FAP results in dissociation of the self-cleavable linker from the chemotherapeutic compound group, followed by protonation of the chemotherapeutic compound group. Thus, the chemotherapeutic compound (parent drug) is released into the extracellular region of the tumor.

[0630] Accordingly, the present invention also relates to a small molecule drug conjugate (SMDC) comprising a chemotherapeutic compound group Ct, a linear or branched self-cleavable linker L, and one, two, three, four or more initiators (F1, F2, F3, F4), wherein

[0631] – L is covalently linked to a nitrogen, amino or oxygen group of Ct;

[0632] – L comprises one, two, three, four or more amino groups;

[0633] – each initiator (F1, F2, F3, F4) is covalently conjugated to an amino group of L;

[0634] – each initiator (F1, F2, F3, F4) can be enzymatically cleaved from L by fibroblast activation protein (FAP);

[0635] – once any one of the initiators (F1, F2, F3, F4) is cleaved, L releases Ct;

[0636] – the initiators (F1, F2, F3, F4) are independent of each other and comprise or have a structure selected from the group consisting of structures comprising the following structures:

[0637]

[0638] wherein the pyrrolidine ring is oriented towards the self-cleavable linker L, X = -H or -CH 3 , Y = -H or -F, -R 1 is a group of a first pharmacokinetic modulating group, and Z is a group having a structure selected from the group consisting of structures (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), (12), (13), (14) and (15), wherein

[0639]

[0640]

[0641] and

[0642] –Ct is a free radical of a chemotherapeutic compound selected from the group consisting of: 1,2,3,4-tetrahydrostaurosporine, avasopasem manganese (17-Dmag), 2-aminopropionitrile, 4SC202, ABBV-CLS 484, abemaciclib, abexinostat, acalabrutinib, acetylbufalin, aderbasib, afatinib, afuresertib, alectinib, alisertib, alpelisib, alvocidib, AMD3465, anlotinib, apalutamide, AR-42, asciminib, atuveciclib, avapritinib, axitinib, AZD7762, BAY1125976, belinostat, β-hydroxyisovaleric acid, BF211, bicalutamide, binimetinib, bortezomib, bosutinib, brigatinib, bufalin, buparlisib, buthionine sulfoximine, cabozantinib, capivasertib, capmatinib, carfilzomib, CEP 9722, ceralasertib, ceritinib, chidamide, CHR-3996, citarinostat, cobimetinib, CompK, copanlisib, crenolanib, crizotinib, CUDC-101, dabrafenib, daclatasvir, dacomitinib, darolutamide, dasatinib, dasatinib D1, dasatinibD2), Dasatinib D3, Dasatinib D4, Decitabine, Defactinib, Degarelix, Diethylstilbestrol, Dinaciclib, Dp44mT, DpC, DUPA, Duvelisib, E7016, Ebvaciclib, Eganelisib, Elimusertib, Emavusertib, Enasidenib, Encorafenib, Enitociclib, Entinostat, Entrectinib, Enzalutamide, Epacadostat, Epigallocatechingallate), Epoxomicin, Erdafitinib, Eribulin, Erlotinib, Everolimus, Fasudil, Fedratinib, Filgotinib, Foslinanib, Fostamatinib, Fruquintinib, Galunisertib, Ganetespib, Gedatolisib, Gefitinib, GFH018, Gilteritinib, Givinostat, Glasdegib, Goserelin, GSK2256098, GSK269962A, GSK690693, GUL, Halofuginone, Hymecromone, Ibrutinib, Icotinib, Idelalisib, Imatinib, Imiquimod, Infigratinib, Iniparib, Ipatasertib, Itacitinib, Ivaltinostat, Ivosidenib, Ixazomib, Kevetrin, Lapatinib, Larotrectinib, Lenalidomide, Leniolisib, Lenvatinib, Leuprolide, Linsitinib, Lonafarnib, Lorlatinib, Losartan, Lucitanib, Luminespib, M1096, Marizomib, ME-344, Merestinib, Metformin, MG132, Midostaurin, Miransertib, Mivavotinib, MK2206, Matrix metalloproteinase 9 inhibitor I (MMP9 Inhibitor I), Mobocertinib, Mocetinostat, Motesanib, MRTX1133, Navitoclax, Nazartinib, Nedisertib, Neratinib, Nilotinib, Nilutamide, Nintedanib, Niraparib, NMS-P118, NMS-P515, NSC668394, NSC95397, Numidargistat, NVP 2, Olaparib, Olmutinib, Omipalisib, Oprozomib, Osimertinib, OTS 964, Palbociclib, Pamiparib, Panobinostat, Paricalcitol, Parsaclisib, Pazopanib, Pemetrexed, Pemigatinib, Pevonedistat, Pexidartinib, Pifusertib, Plerixafor, PMPA, Ponatinib, Practinostat, Pralsetinib, Prednisone, Prexasertib, Prinomastat, Propranolol, Quisinostat, Quizartinib, Ralimetinib, Ravoxertinib, Regorafenib, Relugolix, Resminostat, Resveratrol, Retaspimycin, Retinoic acid, Ribociclib, Ricolinostat, Rigosertib, Ripretinib, RO3306, Rocilinostat, Rogaratinib, Romidepsin, Rucaparib, Ruxolitinib, S2, S5, Saridegib, SBI 0654454, SCH772984, Seliciclib, Selitrectinib, Selpercatinib, Selumetinib, SGN 2FF, SGX393, Shikonin, Silibinin, Sitravatinib, Sonidegib, Sorafenib, Sotorasib, Staurosporine, SU11274, Sunitinib, Surufatinib, Tacedinaline, Tadalafil, Talazoparib, Taletrectinib, Tarloxotinib, Taselisib, Tazemetostat, Tefinostat, Temsirolimus, Tetrazole, Tivozanib, Tofacitinib, Tozasertib, Trametinib, Tranilast, Tretinoin, Trichostatin, Tucatinib, Tucidinostat, Tuvusertib, Ubenimex, Umbralisib, Uprosertib, USL311, Vactosertib, Valproic acid, Valsartan, Vandetanib, Veliparib, Vemurafenib, Venetoclax, Verteporfin, Vismodegib, Vorinostat, WRG28, WZ811, Xevinapant, Zandelisib, Zanubrutinib, ZM447439, Abiraterone, Aclarubicin, Adozelesin, Alrestatin, Amanitin, Amrubicin, Anthramycin, Arenastatin, Bizelesin, Bleomycin, Camptothecin, Capecitabine, Carzelesin, CC 1065, Chaconine, Chlorambucil, Cryptophycin 24, Cyclophosphamide, Cytarabine, Dacarbazine, Dactinomycin, Daunorubicin, DAVLBH, Deruxtecan, Dexamethasone, Dichloro acetic acid, Dimethyl-SGD-1882, Docetaxel, Dolastatin 10, Doxorubicin, Duocarmycin A, Duocarmycin B1, Duocarmycin B2, Duocarmycin C1, Duocarmycin C2, Duocarmycin D, Duocarmycin GA, Duocarmycin SASA), Emetine, Epirubicin, Eribulin, Etoposide, Floxuridine, Fludarabine, Fluorouracil, Flutamide, Fulvestrant, Gemcitabine, Idarubicin, Ifosfamide, Irinotecan, L–Asparaginase, Lomustine, Melphalan, Mertansine, Methotrexate, Milataxel, Mitoxantrone, Monomethyl Auristatin E, Maytansine, Maytansinoid, Ozogamicin, Paclitaxel, Pirarubicin, Pixantrone, Podophyllotoxin, Procarbazine, Rapamycin, Rachelmycin, Salinomycin, SB T 1214, Selinexor, SN 38, Solamargine, Solanine, Talirine, Temozolomide, Tesetaxel, SG3199 (Tesirine), Thapsigargin, Tomatine, Topotecan, Tubulysin B, Valrubicin, Vinblastine, Vincristine, Vinorelbine, VIP126, Zorubicin.

[0643] The convenient implementation mode of the small molecule drug conjugate (SMDC) or prodrug of the present invention has one of the following characteristics, or, without mutual exclusion or contradiction, has a combination of two or more of the following characteristics, specifically as follows:

[0644] –Ct is a group of Dinaciclib;

[0645] –Ct is a group of NVP 2;

[0646] –Ct is a group of Erlotinib;

[0647] –Ct is a group of Imatinib;

[0648] –Ct is a group of Sorafenib;

[0649] –Ct is a group of Bufalin;

[0650] –Ct is a group of Acetylbufalin;

[0651] –The initiators (F1, F2, F3, F4) independently of one another comprise or have a structure selected from the following group of structures, which group includes

[0652]

[0653] wherein the pyrrolidine ring is oriented towards the self-cleavable linker L, Y = -H or -F and X = -H or -CH3;

[0654] –The initiators (F1, F2, F3, F4) independently of one another comprise or have a structure selected from the following group of structures, which group includes

[0655]

[0656] wherein the pyrrolidine ring is oriented towards the self-cleavable linker L

[0657] –Two, three, four or more of the initiators (F1, F2, F3, F4) are different from one another;

[0658] –Two, three, four or more of the initiators (F1, F2, F3, F4) are the same;

[0659] –The small molecule drug conjugate (SMDC) comprises one initiator F1;

[0660] –The small molecule drug conjugate (SMDC) comprises two initiators (F1, F2);

[0661] –The small molecule drug conjugate (SMDC) comprises four initiators (F1, F2, F3, F4);

[0662] –L comprises a linking moiety for linking Ct, said linking moiety having a structure selected from the following group of structures, which group includes

[0663]

[0664] –L contains a linking portion for linking to Ct, and this linking portion has the following structure

[0665]

[0666] wherein the terminal carbonyl group is covalently linked to the nitrogen atom group of Ct;

[0667] –L contains a linking portion for linking to Ct, and this linking portion has the following structure

[0668]

[0669] wherein the terminal carbonyl group is covalently bonded to the amine group of Ct;

[0670] –L contains a linking portion for connecting to Ct, and this linking portion has the following structure

[0671]

[0672] wherein the terminal carbonyl group is covalently bound to the oxygen atom group of Ct;

[0673] –L contains a linking portion for connecting to Ct, and this linking portion has the following structure

[0674]

[0675] wherein the terminal carbonyl group is covalently bonded to the nitrogen-containing group of Ct;

[0676] –L contains a linking portion for connecting to Ct, and this linking portion has the following structure

[0677]

[0678] wherein the terminal carbonyl group is covalently bonded to the amine group of Ct;

[0679] –L contains a linking portion for connecting to Ct, and this linking portion has the following structure

[0680]

[0681] wherein the terminal carbonyl group is covalently bonded to the oxygen radical of Ct;

[0682] –L contains a linking portion for connecting to Ct, and this linking portion has the following structure

[0683]

[0684] Among them, the terminal carbonyl group is covalently bonded to the nitrogen radical of Ct;

[0685] –L contains a linking moiety for linking to Ct, and this linking moiety has the following structure

[0686]

[0687] Among them, the terminal carbonyl group is covalently bonded to the amine radical of Ct;

[0688] –L contains a linking moiety for linking to Ct, and this linking moiety has the following structure

[0689]

[0690] Among them, the terminal carbonyl group is covalently bonded to the oxygen radical of Ct;

[0691] –L contains a linking moiety for linking to Ct, and this linking moiety has the following structure

[0692]

[0693] Among them, the terminal carbonyl group is covalently bonded to the nitrogen radical of Ct;

[0694] –L contains a linking moiety for linking to Ct, and this linking moiety has the following structure

[0695]

[0696] Among them, the terminal carbonyl group is covalently bonded to the amine radical of Ct;

[0697] –L contains a linking moiety for linking to Ct, and this linking moiety has the following structure

[0698]

[0699] Among them, the terminal carbonyl group is covalently bonded to the oxygen radical of Ct;

[0700] –L contains one, two or more branched-chain moieties having the following structure

[0701]

[0702] Among them, the terminal carbonyl group faces Ct or is covalently bonded to Ct;

[0703] –L contains one, two or more branched-chain moieties having the following structure

[0704]

[0705] Among them, the terminal carbonyl group faces Ct or is covalently bound to Ct;

[0706] – L contains one, two, three, four or more linking moieties for the initiators (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure

[0707]

[0708] wherein the terminal amino group is covalently linked to the initiator (F1, F2, F3, F4);

[0709] – L contains one, two, three, four or more linking moieties for the initiators (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure

[0710]

[0711] wherein the terminal amino group is covalently linked to the initiator (F1, F2, F3, F4), and B1 are independently selected from the group consisting of the following moieties

[0712]

[0713] - L contains one, two, three, four or more linking moieties for the initiators (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have a structure selected from the following groups

[0714]

[0715] wherein the terminal amino group is covalently linked to the initiator (F1, F2, F3, F4);

[0716] - L contains one, two, three, four or more linking moieties for the initiators (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure

[0717]

[0718] wherein

[0719] - the terminal amine is covalently linked to the initiator (F1, F2, F3, F4); and

[0720] - r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0721] -L contains one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three or more than four linking moieties each independently have the following structure

[0722]

[0723] wherein the terminal amino group is covalently linked to the initiator (F1, F2, F3, F4);

[0724] -L contains one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three, four or more linking moieties each independently have the following structure

[0725]

[0726] wherein the terminal amine is covalently bound to the initiator (F1, F2, F3, F4);

[0727] -L contains a second pharmacokinetic moiety R 2 ;

[0728] -L contains a second pharmacokinetic moiety R 2 and additionally 1, 2, 3, 4, 5, 6, 7 or 8 pharmacokinetic moieties (R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 );

[0729] -L contains one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three, four or more linking moieties each independently have a structure selected from the group consisting of the following structures (a), (b), (c), (d), (e), (f), (g), (h), (i), (j), (k), (l), (m), (n) and (o), wherein

[0730]

[0731]

[0732] wherein

[0733] -the terminal amine is covalently linked to the initiator (F1, F2, F3, F4);

[0734] - r = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0735] -- A - does not exist, or is selected from the group consisting of: - O -, - NH -, - CH(OH) -, - CO -, - N(CH 3 ) -, - S - and - SH 2 -;

[0736] -- E - is selected from the group consisting of: - CH 2 -, - O -, - NH -, - N(CH 3 ) -, - S - and - SH 2 -;

[0737] - p = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0738] - q = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 and q + s = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10;

[0739] -- R 2 is - H, - CH 3 or a second pharmacokinetic modulating moiety;

[0740] - contains an initiator F1 and a moiety having the following structure

[0741]

[0742] wherein the terminal carbamate is directed towards the initiator F1 and u = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20;

[0743] - L contains two, three, four or more branches, which independently of one another contain an initiator (F1, F2, F3, F4) and a moiety having the following type of structure

[0744] structure

[0745]

[0746] wherein the terminal carbamate is directed towards the initiator (F1, F2, F3, F4), u = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20, and the value of u in one branch may be different from that in other branches;

[0747] - The self-cleaving linker L comprises 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 or more moieties, each of which independently has a structure selected from the group consisting of:

[0748]

[0749] – Each pharmacokinetic moiety (R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 ) is independent of each other, and its structure is selected from the group including the following structures:

[0750] where m = 1, 2, 3, …, 999 or 1000;

[0751] where m = 1, 2, 3, …, 19 or 20;

[0752]

[0753] – Each pharmacokinetic moiety (R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10) are, independently of one another, peptide residues comprising 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 amino acids, the amino acids being independently selected from the group comprising alanine (Ala), arginine (Arg), asparagine (Asn), aspartic acid (Asp), cysteine (Cys), glutamine (Gln), glutamic acid (Glu), glycine (Gly), histidine (His), isoleucine (Ile), leucine (Leu), lysine (Lys), methionine (Met), phenylalanine (Phe), proline (Pro), serine (Ser), threonine (Thr), tryptophan (Trp), tyrosine (Tyr), valine (Val), pyrrolysine (Pyl), selenocysteine (Sec), γ-aminobutyric acid (GABA or γ-Aminobutyric acid), homoserine, dopa (DOPA or 3,4-dihydroxyphenylalanine), citrulline, β-alanine and thyroxine;

[0754] – each pharmacokinetic moiety (R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 ) is, independently of one another, a lactide oligomer residue comprising 4, 5, …, 39 or 40 monomer units;

[0755] – each pharmacokinetic moiety (R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 ) is, independently of one another, a lactide-glycolide copolymer oligomer residue comprising 4, 5, …, 39 or 40 monomer units;

[0756] – each pharmacokinetic moiety (R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7,R 8 ,R 9 ,R 10 ) are, independently of each other, acrylate oligomer residues containing 4, 5, …, 39 or 40 monomer units;

[0757] – each pharmacokinetic moiety (R 1 ,R 2 ,R 3 ,R 4 ,R 5 ,R 6 ,R 7 ,R 8 ,R 9 ,R 10 ) is, independently of each other, a methacrylate oligomer residue containing 4, 5, …, 39 or 40 monomer units.

[0758] In a preferred embodiment, the small molecule drug conjugate (SMDC) or prodrug of the present invention comprises one or more moieties that cover at least a part of at least one or more FAP-activatable initiators and at least a part of a self-cleaving linker, and has a structure of the following type:

[0759]

[0760]

[0761]

[0762] wherein X = -H or -CH3, Y = -H or -F, R 1 is H or a pharmacokinetic modulating group, and the dashed line represents the enzyme cleavage site.

[0763] A preferred embodiment of the small molecule drug conjugate (SMDC) or prodrug of the present invention comprises one or more moieties that independently of each other have the following general formula structure:

[0764]

[0765] wherein Fc represents one of the groups cleavable by FAP described above, G 1 = -O- or -NH-; G 2 = -CH- or -C(CH3)-; preferably G 2 = -CH-; G 3 is selected from the following groups:

[0766]

[0767] Preferably, G 3 = –CH 2–, –CH(CH 3 )–, –O– or –CH=CH–; more preferably, G3 = –CH 2 – or –CH(CH 3 )–.

[0768] Preferred embodiments of the small molecule drug conjugate (SMDC) or prodrug of the present invention comprise one or more moieties which independently of one another have a structure selected from the following group of structures

[0769]

[0770] wherein Fc represents one of the moieties cleavable by fibroblast activation protein (FAP) described throughout the foregoing.

[0771] Moieties of the above type can be efficiently cleaved by fibroblast activation protein (FAP) (the ratio of the catalytic constant to the Michaelis constant kcat / KM > 10 6 s -1 ·M -1 ), and have excellent selectivity for FAP compared to prolyl oligopeptidase (PREP). Unlike FAP, PREP is ubiquitously expressed in healthy tissues. The high selectivity of FAP over PREP limits off-target activation of the prodrug in healthy tissues and the consequent systemic toxicity.

[0772] To increase the spatial probability and efficiency of FAP activation in tumors and the delivery of the parent drug, the present invention further provides prodrugs comprising two, three, four or more initiators cleavable by FAP.

[0773] There is a wide variety of heterobifunctional linkers available on the market, which are sold either as ready-to-use compounds, crosslinking kits, or with related services (for example, available from https: / / www.carbolution.de / , https: / / bezwadabiomedical.com / , https: / / broadpharm.com, https: / / p3bio.com / amino-acids / fmoc-amino-acids / , https: / / www.thermofisher.com, https: / / www.profacgen.com). Some suppliers offer comprehensive libraries containing Fmoc and tert-butyl (tBu) protected amino acids. Thermo Fisher Scientific ( The "Bioconjugation Technical Handbook" (2022; URL: https: / / assets.thermo-fisher.com / TFS-Assets / BID / Handbooks / bioconjugation-technical-handbook.pdf) by (Scientific) introduces numerous linker chemistries and bioconjugation strategies. Commercially available linker compounds offer almost unlimited possibilities for the conventional modification of self-immolative linkers without significantly affecting the key pharmacological properties of the prodrugs of the present invention in a clinically significant manner. Therefore, it should be noted that the partial general description of the self-immolative linker structure in the present invention does not reduce the technical feasibility and medicinal effects of the prodrugs of the present invention.

[0774] U.S. Patent Application Publication No. US 2017 / 0119901 A1 describes the synthesis methods of FAP-activatable prodrugs in paragraphs 401-431 (Examples 1 and 2). The synthesis schemes described in this patent (which have been incorporated by reference into this patent application) enable those skilled in the art to prepare various Fc-L-Ct type FAP-activatable prodrugs in a similar manner.

[0775] The following cited articles further disclose various self-immolative linkers and their preparation methods:

[0776] - A. Alouane, R. Labruère, T. Le Saux, F. Schmidt, L. Jullien; "Self-Immolative Spacers: Kinetic Aspects, Structure–Property Relationships, and Applications"; Angew. Chem. Int. Ed. 2015, 54, 7492–7509; doi:10.1002 / anie.201500088;

[0777] - A. G. Gavriel, M. R. Sambrook, A. T. Russell, W. Hayes; "Recent advances in self-immolative linkers and their applications in polymeric reporting systems"; Polym. Chem., 2022, 13, 3188; doi:10.1039 / d2py00414c;

[0778] - D. Xiao, L. Zhao, F. Xie, S. Fan, L. Liu, W. Li, R. Cao, S. Li, W. Zhong, X. Zhou; "A bifunctional molecule-based strategy for the development of theranostic antibody-drug conjugate"; "Theranostics" 2021, 11(6): 2550 - 2563; doi:10.7150 / thno.51232.

[0779] The technical content in the articles by Alouane et al., Gavriel et al., and Xiao et al. is incorporated herein by reference.

[0780] In the present invention, the terms "small molecule drug conjugate", "SMDC", and "prodrug" are synonymous and refer to a compound that includes one or more initiators or trigger moieties activatable by fibroblast activation protein (FAP), a linear or branched self-cleavable linker moiety, and a group or residue of a chemotherapeutic compound, wherein the self-cleavable linker is located between the group or residue of the chemotherapeutic compound and the one or more initiators or trigger moieties.

[0781] The term "activatable by fibroblast activation protein (FAP)" is interpreted as the catalytic (i.e., rapid and efficient) cleavage of the initiator or trigger moiety from the self-cleavable linker. The cleavage efficiency is usually expressed in units of [s-1·M-1] as the ratio of the catalytic rate constant kcat to the Michaelis constant KM, kcat / KM (see https: / / en.wikipedia.org / wiki / Michaelis-Menten_kinetics). kcat and KM can be readily determined by well-known enzyme assay techniques.

[0782] In the present invention, the term "residue of..." or "group of..." refers to a compound having at least one unpaired valence electron (see https: / / en.wikipedia.org / wiki / Radical_(chemistry)).

[0783] "Residue of a chemotherapeutic compound" or "group of a chemotherapeutic compound" refers to a chemotherapeutic compound from which a positively charged hydrogen ion has been removed. The term "protonation" refers to the addition of a positively charged hydrogen ion to the group or residue of a chemotherapeutic compound.

[0784] The entire content of all prior art documents cited in this patent application is incorporated by reference. In particular, the chemical synthesis methods described in the cited prior art documents can be used directly or in a similar and appropriately adjusted manner for preparing the prodrugs of the present invention. Examples

[0785] Example 1: Synthesis of the cleavable moiety of fibroblast activation protein (FAP) conjugated with a self-cleaving linker

[0786] The general synthetic route outlined in Scheme 1 below is based on:

[0787] A. De Decker, G. Vliegen, D. Van Rompaey, A. Peeraer, A. Bracke, L. Verckist, K. Jansen, R. Geiss-Friedlander, K. Augustyns, H. De Winter, I. De Meester, A. M. Lambeir, P. Van der Veken, "Novel Small Molecule-Derived, Highly Selective Substrates for Fibroblast Activation Protein (FAP)", ACS Med. Chem. Lett. 2019, Vol. 10, No. 8, pp. 1173-1179.

[0788]

[0789] X = H or F, Xaa = Gly or D-Ala

[0790] LP = Self-cleaving linker residue with a protecting group

[0791] e.g.

[0792] Scheme 1: Synthesis of Fibroblast Activation Protein (FAP) Cleavable Moiety and Self-Cleaving Linker Conjugates

[0793] The commercially available compound 1 (i.e., Boc-L-proline or Boc-4,4-difluoro-L-proline) is coupled with the protected self-cleaving linker precursor NH 2 -LP (see also Example 2). The resulting compound 2 is deprotected to give the intermediate 3. The latter is coupled with Boc-protected D-alanine or glycine to give the protected conjugate 4. The compound 4 is deprotected by acidolysis to give the intermediate 5, and the conjugate 6 is synthesized from the intermediate 5 by acylating the free amino group with quinoline-4-carboxylic acid.

[0794] Reagents and reaction conditions:

[0795] (a) 1-chloro-N,N,2-trimethyl-1-propenylamine, triethylamine (TEA), dichloromethane (DCM): tetrahydrofuran (THF) (1:1), room temperature;

[0796] (b) Hydrogen chloride (HCl) or trifluoroacetic acid (TFA), dichloromethane (DCM), room temperature;

[0797] (c) Boc-Xaa (Boc-protected amino acid, Xaa represents an amino acid residue), propylphosphonic anhydride (T 3 P), N,N-diisopropylethylamine (DIPEA), dichloromethane, room temperature;

[0798] (d) Trifluoroacetic acid (TFA), dichloromethane (DCM), room temperature;

[0799] (e) Quinoline-4-carboxylic acid, propylphosphonic anhydride (T 3 P), N,N-diisopropylethylamine (DIPEA), dichloromethane (DCM).

[0800] As shown in Scheme 1, the self-cleaving linker precursor NH 2 -LP can be easily prepared by reducing commercially available 6-amino-2-oxochromene-3-carboxylic acid (CAS No. 91587-88-1) with LiAlH 4 .

[0801] Example 2: Synthesis of a coumarin-based self-cleaving linker and its conjugation with the cleavable moiety of FAP

[0802] The synthesis outlined in Scheme 2 below is based on:

[0803] R. Weinstain, E. Segal, R. Satchi-Fainarob, D. Shabat, "Real-time monitoring of drug release", Chem. Commun., 2010, Vol. 46, pp. 553-555;

[0804] N.C. Lim, J.V. Schuster, M.C. Porto, M.A. Tanudra, L. Yao, H.C. Freake, C. Brückner, "Coumarin-Based Chemosensors for Zinc(II): Toward the Determination of the Design Algorithm for CHEF-Type and Ratiometric Probes", *Inorganic Chemistry*, 2005, Vol. 44, No. 6, pp. 2018 - 2030.

[0805]

[0806] Scheme 2: Synthesis of Coumarin-Based Self-Cleavable Linkers and Conjugation to the Cleavable Moiety of Fibroblast Activation Protein (FAP)

[0807] (i) 2,4-Dihydroxybenzaldehyde 7 (0.74 g, 5.36 mmol) was dissolved in ethanol (15 mL). Diethyl glutaconate (1.0 mL, 5.65 mmol) was added, followed by the dropwise addition of 3 drops of piperidine dried over KOH pellets. The resulting solution was refluxed for 24 h. The reaction mixture was allowed to cool slowly to room temperature and then cooled to -20 °C. The yellow crystals that precipitated were filtered and dried to give ethyl 3-(7-hydroxy-2-oxo-2H-chromen-3-yl)acrylate 8 (1.24 g, 89% yield).

[0808] (ii) Ethyl acrylate 8 (0.200 g, 0.77 mmol) was dissolved in dry pyridine (4 mL), and acetic anhydride (4 mL) was added. The reaction mixture was stirred at ambient temperature for 0.5 h, then poured into ice and stirred for an additional 10 min. The white precipitate that formed was filtered and dried to give ethyl 3-(7-acetoxy-2-oxo-2H-chromen-3-yl)acrylate 9 (0.210 g, 90% yield).

[0809] (iii) Ethyl acrylate 9 (2.20 g, 7.28 mmol) was dissolved in THF (200 mL). 4 OsO 4 (2 mL of 4% w / w aqueous solution) was added, and the mixture was stirred for 0.5 h. 2 NaIO 2Partition. The organic layer was evaporated to dryness by rotary evaporation. Column chromatography (silica gel, eluent from CH 2 Cl 2 gradient to CH 2 Cl 2 / 5% CH 3 CN) was used to separate the intermediate 3-formyl-2-oxo-2H-chromene-7-yl acetate 10 as a white solid (1.40 g, yield 83%).

[0810] (iv) Ester 10 (620 mg, 2.66 mmol) was dissolved in 32% NH 4 OH aqueous solution, and acetonitrile (MeCN) was slowly added until the reaction mixture was homogeneous. The reaction was monitored by thin-layer chromatography (TLC, ethyl acetate: n-hexane = 1:1) until completion (20 minutes). Ethyl acetate was added, and the solution was washed twice with 1 M HCl. The organic phase was dried over MgSO 4 and then filtered, and the solvent was removed under reduced pressure to give compound 11 (456 mg, yield 90%).

[0811] (v) Compound 11 was coupled with the FAP-cleavable moiety Fci through the formation of a common amide (peptide) bond to give compound 12.

[0812] (vi) Conjugate 12 (100 mg, 0.53 mmol, 1 eq) was dissolved in methanol (4 mL), and sodium borohydride (30 mg, 0.79 mmol, 1.5 eq) was added. The reaction was monitored by thin-layer chromatography (TLC, ethyl acetate: n-hexane = 1:1) until completion (10 minutes). The reaction mixture was diluted with ethyl acetate, washed once with saturated NH 4 Cl solution, dried over MgSO 4 and then filtered, and the solvent was removed under reduced pressure. The crude product was purified by silica gel column chromatography (ethyl acetate: n-hexane = 1:1) to give compound 13 (yield 70 - 86%).

[0813] Example 3: Synthesis of 7-amino-3-(1-hydroxyethyl)-2H-chromen-2-one

[0814] The synthetic route shown in Scheme 3 below is based on: "A bifunctional molecule-based strategy for the development of theranostic antibody-drug conjugate" by D. Xiao, L. Zhao, F. Xie, S. Fan, L. Liu, W. Li, R. Cao, S. Li, W. Zhong, X. Zhou, published in Theranostics 2021, Vol. 11, No. 6: 2550-2563; doi: 10.7150 / thno.51232.

[0815]

[0816] Scheme 3: Synthesis of 7-amino-3-(1-hydroxyethyl)-2H-chromen-2-one

[0817] Synthesis of 3-acetyl-7-nitro-2H-chromen-2-one (1): To a stirred mixture of 2-hydroxy-4-nitrobenzaldehyde (5.00 g, 30 mmol) and ethyl acetoacetate (4.6 mL, 36 mmol) was added 349 μL of piperidine. After refluxing for 1.5 h, the pale yellow solid precipitate was filtered out and then washed with ethanol to give Intermediate 1 (4.00 g, yield 57.1%).

[0818] Synthesis of 3-(1-hydroxyethyl)-7-nitro-2H-chromen-2-one (2): At 0 °C, sodium borohydride (390 mg, 10.30 mmol) and cerium chloride (2.54 g, 10.3 mmol) were added to a solution of Intermediate 1 (2.40 g, 10.30 mmol) in methanol and tetrahydrofuran (volume ratio 1:1, total volume 200 mL). After the reaction was completed within 1.5 h, the solvent was concentrated under reduced pressure, and the crude product was purified by column chromatography (ethyl acetate / n-hexane = 1:1.5) to give yellow solid Intermediate 2 (1.80 g, yield 74.3%).

[0819] Synthesis of 7-amino-3-(1-hydroxyethyl)-2H-chromen-2-one (3): Intermediate 2 (500 mg, 2.13 mmol), iron(III) chloride hexahydrate (115 mg, 0.45 mmol), hydrazine hydrate (1.50 g, 25.6 mmol) and activated carbon (305 mg, 25.6 mmol) were mixed in anhydrous ethanol (30 mL) and refluxed for 2 h. The solution was filtered, and the filtrate was concentrated under reduced pressure. The crude product was purified by column chromatography (ethyl acetate / n-hexane = 1:1) to give white solid 3 (300 mg, yield 68.8%).

[0820] Example 4: Ether bond formation between different alcohols

[0821] The synthetic route outlined in Scheme 4 below is based on:

[0822] P.K. Sahoo, S.S. Gawali, C. Gunanathan, "Iron-Catalyzed Selective Etherification and Trans etherification Reactions Using Alcohols", *ACS Omega*, 2018, Vol. 3, pp. 124 - 136.

[0823]

[0824] R 1 = aryl, R 2 , R 3 = alkyl or aryl

[0825] Scheme 4: Iron(III)-Catalyzed Etherification of Two Different Alcohols

[0826] Secondary alcohol (0.5 mmol), primary alcohol (0.5 mmol), Fe(OTf) 3 (0.025 mmol, 5 mol%), and NH 4 Cl (0.025 mmol, 5 mol%) in DCM (2 mL) are heated at 45 °C for 1 to 24 h. When using Fe(NO 3 ) 3 ·9H 2 O (0.025 mmol, 5 mol%) as the catalyst, the reaction is carried out at 70 °C. The product is purified and separated by column chromatography, and the typical yield is between 40% and 93%.

[0827] Example 5: Coupling of alcohol with amine via N-O bond formation

[0828] The reaction strategies outlined in Schemes 5a - 5e below are based on:

[0829] Hettikankanamalage, D. Crich, "Diversity-Oriented Synthesis of N,N,O-Trisubstituted Hydroxylamines from Alcohols and Amines via N - O Bond Formation" Hydroxylamines from Alcohols and Amines by N-O Bond Formation), Journal of the American Chemical Society (J. Am. Chem. Soc.) 2020, Vol. 142, pp. 14820 - 14825.

[0830]

[0831] Scheme 5a: Synthesis of 2-Hydroperoxytetrahydro-2H-pyran

[0832] At 0 °C, H 2 SO 4 (18.4 M, 0.05 mL, 0.92 mmol, 0.01 eq) was added to a stirred solution of H 2 O 2 (50% v / v) (3.8 mL, 58.8 mmol, 2 eq). The solution was stirred for 10 minutes, then 3,4-dihydropyran (2.68 mL, 29.4 mmol, 1 eq) was added dropwise at 0 °C and stirring was continued for 1 hour. Subsequently, the reaction mixture was diluted with Et 2 O (15 mL) and the reaction was quenched by the addition of saturated NH 4 Cl (30 mL) solution. The resulting two-phase mixture was transferred to a separatory funnel and the layers were separated. The aqueous layer was extracted with ethyl acetate (5 × 40 mL), the organic layers were combined, dried over Na 2 SO 4 , filtered, and then concentrated in vacuo. The resulting residue was purified by flash column chromatography on silica gel (eluent: ethyl acetate: n-hexane = 5:95) to afford 2-hydroperoxytetrahydro-2H-pyran as a colorless oil (2.04 g, 17.3 mmol, 59% yield).

[0833]

[0834] Scheme 5b: Synthesis of 2-Hydroperoxy-2-methyltetrahydro-2H-pyran (MTHP)

[0835] Under an argon atmosphere, a 3.0 M solution of CH 3 MgCl in tetrahydrofuran (THF) (20 mmol, 6.67 mL, 1.0 eq) was added dropwise over 10 minutes to a solution of δ-valerolactone (20 mmol, 1.86 mL, 1.0 eq) dissolved in 40 mL of anhydrous THF at -40 °C. The reaction was stirred at -40 °C for 1 hour. After the starting materials were consumed as indicated by thin-layer chromatography (TLC) and mass spectrometry (MS), the reaction mixture was warmed to -20 °C and quenched with saturated NH 4The reaction was quenched with Cl solution (40 mL), and then diluted with deionized water (20 mL) at room temperature. The resulting two-phase mixture was separated, and the aqueous layer was extracted with ethyl acetate (5 × 40 mL). The organic layers were combined, dried over Na 2 SO 4 , filtered, and then concentrated in vacuo. The crude reaction mixture was used directly in the subsequent step without further purification.

[0836] At 0 °C, sulfuric acid (18.4 M, 109 μL, 2.0 mmol, 0.10 equiv) was added to a solution of 2-methyl-tetrahydro-2H-pyran-2-ol (2.3 g, 20 mmol, 1 equiv) in 100 mL of dichloromethane (DCM) under stirring. An aqueous hydrogen peroxide solution (50% w / w) (6.8 mL, 100 mmol, 5.00 equiv) was added dropwise over 5 minutes, and stirring was continued at 0 °C for 10 minutes. The reaction was warmed to room temperature and stirred for 2 hours. The reaction was quenched with saturated NH 4 Cl solution (40 mL), the resulting two-phase mixture was separated, and the aqueous layer was extracted with ethyl acetate (5 × 40 mL). The organic layers were combined, dried over Na 2 SO 4 , filtered, and then concentrated in vacuo. The resulting residue was purified by flash column chromatography on silica gel (eluent: dichloromethane (DCM) 0:100 - ethyl ether (Et 2 O): dichloromethane 8:92) to give 2-hydroperoxy-2-methyltetrahydro-2H-pyran as a clear colorless oil (1.72 g, 13.0 mmol, 65% overall yield).

[0837]

[0838] Scheme 5c: Synthesis of Tetrahydropyran (THP) and 2-Hydroperoxy-2-Methyltetrahydro-2H-Pyran (MTHP) Monoperoxy Acetals of Simple Alcohols

[0839] Under an argon atmosphere at 0 °C, anhydrous DCM (0.17 - 0.60 M), alcohol (1.0 equiv), and base (1.5 equiv) were added to an oven-dried flask. The solution was stirred for 10 minutes, and then Tf 2 O (1.2 - 1.5 equiv) was added dropwise. The solution was stirred at 0 °C for 30 to 60 minutes. Then, 10% HCl (10 mL) was added, and the layers were separated. The organic layer was washed with saturated NaHCO 3 (1 × 10 mL). The aqueous layer was extracted with EtOAc (3 × 5 mL), the organic layers were combined, washed again with saturated NaCl solution (1 × 10 mL), and dried over MgSO 4Dry, filter, and then concentrate in vacuo. The triflate was isolated by flash silica gel column chromatography (eluent: EtOAc: n-hexane) and used in the next reaction.

[0840] Under an argon atmosphere (protected by a balloon), lithium tert-butoxide or potassium tert-butoxide (1.2 - 1.5 equiv) was added in one portion to a solution of THP or MTHP (1.0 - 2.0 equiv) stirred in anhydrous THF (0.2 - 0.5 M). The solution was stirred at 0 °C for 10 minutes, and then a portion of the triflate obtained in the previous step (1.0 - 2.0 equiv) was added dropwise via syringe. The solution was stirred at 0 °C for 1 h, then the mixture was allowed to warm to room temperature and stirring was continued for 1 - 24 h. The reaction mixture was quenched with NaHCO 3 (20 mL) and diluted with EtOAc (10 mL). The layers were separated, and the aqueous layer was extracted with EtOAc (3 × 5 mL). The organic layers were combined, dried over MgSO 4 / Na 2 SO 4 dried, filtered, and then concentrated in vacuo. The monoperoxyacetal was obtained by flash silica gel column chromatography (eluent: EtOAc: n-hexane).

[0841]

[0842] Scheme 5d: Synthesis of 2-hydroperoxy-2-methyltetrahydro-2H-pyran (MTHP) monoperoxyacetals of complex alcohols

[0843] Under an argon atmosphere at 0 °C, anhydrous DCM (0.13 - 0.50 M), alcohol (1.0 equiv), and pyridine (2.0 equiv) were added to an oven-dried flask. The solution was stirred for 10 minutes, and then Tf 2 O (1.2 - 1.5 equiv) was added dropwise. The solution was stirred at 0 °C for 30 to 60 minutes, and then a few drops of MeOH and 10% HCl (1 × 10 mL) were added for dilution. The layers were separated, and the organic layer was washed with saturated NaHCO 3 (1 × 10 mL). The aqueous layer was extracted with EtOAc (3 × 5 mL), the organic layers were combined, washed with saturated NaCl solution (1 × 10 mL), dried over MgSO 4 dried, filtered, and then concentrated in vacuo. The triflate was isolated by flash silica gel column chromatography (eluent: EtOAc: n-hexane) and used in the next reaction.

[0844] Under an argon atmosphere, NaH (60% dispersed in mineral oil, 1.2 - 1.5 equivalents) was added in one portion to a stirred solution of MTHP (1.0 equivalent) in anhydrous DMF. The solution was stirred at 0 °C for 10 minutes, after which the triflate obtained in the previous step (1.3 equivalents) was added dropwise via syringe. The solution was stirred for 1 hour. The mixture was allowed to stand at room temperature and stirring was continued for 1 - 16 hours. Then the reaction mixture was diluted with EtOAc (10 mL) and the reaction was quenched with saturated NaHCO 3 (10 mL). The layers were separated and the aqueous layer was extracted with EtOAc (3 × 5 mL). The organic layer was dried over Na 2 SO 4 / MgSO 4 and filtered, then concentrated in vacuo. The monoperoxyacetal was isolated by flash column chromatography on silica gel (eluent: EtOAc: n - hexane).

[0845]

[0846] Scheme 5e: Synthesis of N,N,O - trisubstituted hydroxylamines containing an N - O bond

[0847] Under an argon atmosphere and at 0 °C, the amine (0.25 - 11.0 mmol, 2.5 equivalents) and 0.25 - 11.0 mL of anhydrous THF were added to an oven - dried or flame - dried flask. EtMgBr (3 M solution in diethyl ether, 0.2 - 8.7 mmol, 2.0 equivalents) was added dropwise to this solution and the reaction mixture was stirred at 0 °C for 10 - 30 minutes (a large amount of gas is generated during the formation of the magnesium amide, so great care is required for large - scale reactions). Subsequently, under an argon atmosphere and at 0 °C, the magnesium amide was transferred via syringe to a solution of THP or MTHP monoperoxyacetal (0.10 - 4.36 mmol, 1.0 equivalent) stirred in another 0.25 - 11.0 mL of anhydrous THF (total concentration 0.2 M). The solution was stirred until TLC and MS indicated complete consumption of the starting materials, after which the reaction mixture was quenched with ice - water and the layers were separated. The aqueous layer was extracted with EtOAc, the organic phases were combined, dried over MgSO 4 / Na 2 SO 4 and filtered, then concentrated in vacuo. The N,N,O - trisubstituted hydroxylamine was obtained by flash column chromatography on silica gel or neutral alumina (eluent: EtOAc: n - hexane or DCM:EtOAc).

[0848] Example 6: Formation of amide bond

[0849] Scheme 6 shows a general example of an amide coupling reaction.

[0850]

[0851] Scheme 6: Amide Coupling Reaction

[0852] Due to the almost infinite variety of readily accessible carboxylic acids and amine derivatives, the amide coupling strategy opens up a simple route for the synthesis of novel compounds. Many reagents and protocols for amide coupling are well-known to those skilled in the art. The most common amide coupling strategies are based on the condensation reaction of carboxylic acids with amines. For this purpose, the carboxylic acid usually needs to be activated. Before activation, the remaining functional groups need to be protected. This reaction proceeds in two steps and can either directly convert the activated carboxylic acid in a single reaction medium (one-pot method) or be carried out in two steps by first isolating the "captured" activated carboxylic acid and then reacting it with the amine.

[0853] In this process, the carboxylic acid reacts with a coupling agent to form a reactive intermediate, which can exist in an isolated form or react directly with the amine. There are many reagents available for the activation of carboxylic acids, such as acyl halides (acyl chlorides, acyl fluorides), azides, acid anhydrides, or carbodiimides. In addition, the reactive intermediate formed can be an ester, such as pentafluorophenyl ester or N-hydroxysuccinimide ester. The intermediates formed from acyl chlorides or azides are highly reactive. However, the harsh reaction conditions and high reactivity often pose an obstacle to their use with sensitive substrates or amino acids. In contrast, the amide coupling strategy using carbodiimides (such as dicyclohexylcarbodiimide (DCC) or diisopropylcarbodiimide (DIC)) has a wide range of applications. Usually, especially in solid-phase synthesis, additives are used to improve the reaction efficiency. Ammonium salts are highly efficient peptide coupling reagents with short reaction times and extremely low degrees of racemization. When using certain additives (such as 1-hydroxybenzotriazole (HOBt)), racemization cannot be completely avoided. To prevent the overreaction of ammonium salts with the free amines of peptides, they need to be used in equimolar amounts with the carboxylic acid. Phosphonium salts react with carboxylates, which usually requires two equivalents of base (such as N,N-diisopropylethylamine (DIEA)). A significant advantage of phosphonium salts over iminium salt reagents is that phosphonium salts do not react with the free amino groups of the amine component. This allows the coupling of acids and amines in a certain molar ratio, helps prevent the intramolecular cyclization of linear peptides, and avoids the overuse of expensive amine components.

[0854] For a detailed summary of the reaction strategies and reagents for amide coupling, the following review articles can be consulted:

[0855] – "Analysis of Past and Present Synthetic Methodologies on Medicinal Chemistry: Where Have All the New Reactions Gone?"; D.G. Brown, Journal of Medicinal Chemistry (J. Med. Chem.) 2016, Vol. 59, pp. 4443 - 4458;

[0856] – “Peptide Coupling Reagents, More than a Letter Soup”; A. El - Faham, F. Albericio; Chemical Reviews (Chem. Rev.) 2011, Vol. 111, pp. 6557 - 6602;

[0857] – “Rethinking amide bond synthesis”; V. R. Pattabiraman, J. W. Bode; Nature, Vol. 480 (2011), issue of 22 / 29;

[0858] – “Amide bond formation: beyond the myth of coupling reagents”; E. Valeur, M. Bradley; Chemical Society Reviews (Chem. Soc. Rev.), 2009, Vol. 38, pp. 606 - 631.

[0859] Example 7: Innovative prodrug with a single fibroblast activation protein (FAP)-activatable initiator

[0860] Schemes 7a - 7m show exemplary prodrugs with a single FAP - activatable initiator. The dashed lines represent FAP - enzymatic cleavage and release of the drug from the self - cleavable linker.

[0861]

[0862] Scheme 7a: Ct is 2 - aminopropanenitrile radical

[0863]

[0864] Scheme 7b: Ct is β - hydroxyisovaleric acid radical

[0865]

[0866] Scheme 7c: Ct is dichloroacetic acid radical

[0867]

[0868] Scheme 7d: Ct is ibrutinib radical

[0869]

[0870] Scheme 7e: Ct is the iniparib radical

[0871]

[0872] Scheme 7f: Ct is the capecitabine radical

[0873]

[0874] Scheme 7g: Ct is the lenalidomide radical

[0875]

[0876] Scheme 7h: Ct is the lenalidomide radical

[0877]

[0878] Scheme 7i: Ct is the lenalidomide radical

[0879]

[0880] Scheme 7j: Ct is the SG3199 radical

[0881]

[0882] Scheme 7j: Ct is the SG3199 radical

[0883]

[0884] Scheme 7k: Ct is the SGN-2FF radical

[0885]

[0886] Scheme 7m: Ct is the tetrazole radical

[0887] Example 8: Innovative prodrug with two fibroblast activation protein (FAP)-activatable initiators

[0888] Schemes 8a - 8c illustrate exemplary prodrugs having two FAP-activatable initiators. The dashed lines represent FAP-catalyzed cleavage and release of the drug from the self-cleaving linker.

[0889]

[0890] Scheme 8a: Ct is the desacetylvinblastine monohydrazide (DAVLBH) radical

[0891]

[0892] Scheme 8b: Ct is the floxuridine radical

[0893]

[0894] Scheme 8c: Ct is the palbociclib radical

Claims

1. A prodrug comprising a chemotherapeutic compound radical Ct, a linear or branched self-cleavable linker L, and one, two, three, four or more initiators (F1, F2, F3, F4), wherein: – L is covalently bound to the nitrogen radical, amine radical or oxygen radical of Ct; – L contains one, two, three, four or more amine radicals; – each initiator (F1, F2, F3, F4) is covalently bound to the amine radical of L; – each initiator (F1, F2, F3, F4) is designed to be enzymatically cleaved from L by fibroblast activation protein (FAP); – L is designed to release Ct upon cleavage of any one of the initiators (F1, F2, F3, F4); – the initiators (F1, F2, F3, F4) independently of one another comprise or have a structure selected from the following group of structures wherein the terminal carbonyl is covalently bound to the amine radical of the self-cleaving linker L, X is -H or -CH 3 , Y is -H or -F, -R1 is the radical of the first pharmacokinetic modulating moiety, and Z is a moiety having a structure selected from the group consisting of structures (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), (12), (13), (14), (15), (16), (17), (18), (19), (20), (21), (22), (23), (24), and (25), wherein and Ct is a free radical of a chemotherapeutic compound selected from the group consisting of: 1,2,3,4-tetrahydrostaurosporine, avispirocin hydrochloride, 2-aminopropionitrile, 4SC202, ABBV-CLS 484, abemaciclib, abexinostat, acalabrutinib, acetylcinobufagin, adebatim, afatinib, avrasertib, alectinib, alisertib, alpelisib, avasimibe, AMD3465, anlotinib, apalutamide, AR-42, asimicinib, atuvicilib, avapritinib, axitinib, AZD7762, BAY1125976, belinostat, β-hydroxyisovaleric acid, BF211, bicalutamide, binimetinib, bortezomib, bosutinib, brigatinib, cinobufagin, buparlisib, buthionine sulfoximine, cabozantinib, capivasertib, crizotinib, carfilzomib, CEP9722, Celasib, Ceritinib, Chidamide, CHR-3996, Sitacstat, Cobimetinib, CompK, Coupanisib, Ceranib, Crizotinib, CUDC-101, Dabrafenib, Daclatasvir, Dacomitinib, Darolutamide, Dasatinib, Dasatinib-D1, Dasatinib-D2, Dasatinib-D3, Dasatinib-D4, Decitabine, Difatinib, Degarelix, Diethylstilbestrol, Denacil, Dp44mT, DpC, DUPA, Duvelisib, E7016, E Visilib, agalisib, elimosibutib, emavisetib, ensipine, encofenib, enetocilib, entinostat, entrectinib, enzalutamide, icadolstat, epigallocatechin gallate, epoxomicin, erdafitinib, eribulin, erlotinib, everolimus, fasudil, fedalatinib, filgotinib, fostananib, fostrinib, fruquintinib, galutinib, ganitaspilib, gefitinib, GFH018, gilteritinib, gevinorestat, glasgib, goserelin, GSK2256098, GSK269962A, GSK690693, GUL, halofuginone, hydroxymethylcoumarin, ibrutinib, icotinib, idelalisib, imatinib, imiquimod, infigratinib, iniparib, ipatinib, itatinib, ivatinib, ivosidenib, ixazomib, kevitrin, lapatinib, larotrectinib, lenalidomide, raniroxib, lenvatinib, leuprolide, linsitinib, lonafarnib, lorlatinib, losartan, ruxitanib, lumiraspirib, M 1096, Marizumab, ME-344, Meritinib, Metformin, MG132, Midostaurin, Mirancitinib, Mivatinib, MK2206, Matrix Metalloproteinase 9 Inhibitor I, Mobotinib, Moxistat, Motesanib, MRTX1133, Navitoclax, Nazartinib, Nedecitib, Neratinib, Nilotinib, Nilutamide, Nintedanib, Niraparib, NMS-P118, NMS-P515, NSC668394, NSC95397, Numidagistat, NVP 2. Olaparib, Omotinib, Omipalixib, Oprazomib, Osimertinib, OTS 964, Palbociclib, Pamiparib, Panobinostat, Paricalcitol, Pasalicib, Pazopanib, Pemetrexed, Pemitinib, Pevonestastat, Pesidatinib, Pifsetinib, Plexafor, PMPA, Ponatinib, Pracista, Pratinib, Prednisone, Presatinib, Prilinastat, Propranolol, Quisinostat, Quizartinib, Relimetinib, Lavotinib, Regorafenib, Relugoli, Resmistat, Resveratrol, Retamycin, Retinoic Acid, Ribociclib, Ricolimustib, Rigosetib, Ripretinib, RO 3306, rocillinstat, rogatinib, romidepsin, rucaparib, ruxolitinib, S2, S5, selegilide, SBI0654454, SCH772984, celiacib, celiacib, selpatinib, selumetinib, SGN 2FF, SGX393, shikonin, silybin, sitratinib, sonidegi, sorafenib, sotolasib, staurosporine, SU11274, sunitinib, sorafenib, tadalafil, tarazopali, talotinib, taselixib, tazemestat, terfestat, temsirolimus, tetrazosole, tivozanib, tofacitinib, tozastatin, trametinib, tranilast, tretinoin, trichostatin, tucatinib, cedabenamide, tuvosetinib, ubenimex, ublixib, uprosalib, USL311, vastatinib, valproic acid, valsartan, vandetanib, veliparib, vemurafenib, veneclav, verteporfin, vismodegib, vorinostat, WRG 28, WZ811, sivanapan, zandecitab, zanubrutinib, ZM447439, abiraterone, aclarubicin, adolesin, alestatin, amanitin, amrubicin, anthramycin, arenastatin, biezeresin, bleomycin, camptothecin, capecitabine, carzelesin, CC 1065, solanine, chlorambucil, cryptophycin 24, cyclophosphamide, cytarabine, dacarbazine, actinomycin D, daunorubicin, acetylvinblastine hydrazide, detrastuzumab, dexamethasone, dichloroacetic acid, dimethyl-SGD-1882, docetaxel, dolastatin 10, doxorubicin, dukamicin A, dukamicin B1, dukamicin B2, dukamicin C1, dukamicin C2, dukamicin D, dukamicin GA, dukamicin SA, emetine, Epirubicin, eribulin, etoposide, floxuridine, fludarabine, fluorouracil, flutamide, fulvestrant, gemcitabine, idarubicin, ifosfamide, irinotecan, L-asparaginase, lomustine, melphalan, maytansine, methotrexate, mitasevac, mitoxantrone, monomethyl auristatin E, maytansine, maytansine compounds, ozogamicin, paclitaxel, pirarubicin, picron, podophyllotoxin, procarbazine, rapamycin, razithromycin, salinomycin, SB T 1214, selinexor, SN 38, australopithecin, solanine, talirelin, temozolomide, tecitaxel, SG3199 (tecitrelin), thapsigargin, tomatine, topotecan, tubulysin B, valrubicin, vinblastine, vincristine, vinorelbine, VIP126, zorubicin.

2. The prodrug according to claim 1, characterized in that Ct is a radical of acetylcinobufagin, cinobufagin, dinaciclib, erlotinib, ibrutinib, imatinib, lenalidomide, NVP 2, osimertinib, palbociclib or sorafenib.

3. The prodrug according to claim 1 or 2, characterized in that the initiators (F1, F2, F3, F4) independently of one another comprise or have a structure selected from the following group of structures wherein the terminal carbonyl group is covalently linked to the amine radical of the self-cleavable linker L, Y = -H or -F, and X = -H or -CH 3 .

4. The prodrug according to claim 1, 2 or 3, characterized in that the initiators (F1, F2, F3, F4) independently of one another comprise or have a structure selected from the following group of structures wherein the terminal carbonyl is covalently bound to the amine radical of the self-cleavable linker L.

5. The prodrug according to any one of claims 1 to 4, characterized in that two, three, four or more of the initiators (F1, F2, F3, F4) are different from one another.

6. The prodrug according to any one of claims 1 to 5, characterized in that two, three, four or more of the initiators (F1, F2, F3, F4) are the same.

7. The prodrug according to any one of claims 1 to 6, characterized in that it comprises one initiator F1.

8. The prodrug according to any one of claims 1 to 6, characterized in that it comprises two initiators (F1, F2).

9. The prodrug according to any one of claims 1 to 6, characterized in that it comprises four initiators (F1, F2, F3, F4).

10. The prodrug according to any one of claims 1 to 9, characterized in that L comprises a linking moiety for linking Ct, and the linking moiety has a structure selected from the following group of structures 11. The prodrug according to any one of claims 1 to 9, characterized in that L comprises a linking moiety for linking Ct, and the linking moiety has the following structure wherein the terminal carbonyl is covalently bound to the nitrogen radical of Ct.

12. The prodrug according to any one of claims 1 to 9, characterized in that L comprises a linking moiety for linking Ct, and the linking moiety has the following structure wherein the terminal carbonyl is covalently bound to the amine radical of Ct.

13. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the oxygen radical of Ct.

14. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the nitrogen radical of Ct.

15. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the amine radical of Ct.

16. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the oxygen radical of Ct.

17. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the nitrogen radical of Ct.

18. The prodrug according to any one of claims 1 to 9, characterized in that L contains a coupling moiety for linking to Ct, and the coupling moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the amine radical of Ct.

19. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the oxygen radical of Ct.

20. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the nitrogen radical of Ct.

21. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the amine radical of Ct.

22. The prodrug according to any one of claims 1 to 9, characterized in that L contains a linking moiety for linking to Ct, and the linking moiety has the following structure wherein the terminal carbonyl group is covalently bonded to the oxygen radical of Ct.

23. The prodrug according to any one of claims 1 to 9, characterized in that L contains a moiety having the following structure where P 10 is covalently linked to Ct, and when 2 ≤ j ≤ h and 2 ≤ h ≤ 10, each part P j is independently selected from the following groups and, when h < j ≤ 10, P j does not exist.

24. The prodrug according to any one of claims 1 to 23, characterized in that L contains one, two or more branched moieties having the following structure wherein the terminal carbonyl group faces Ct or is covalently bonded to Ct.

25. The prodrug according to any one of claims 1 to 23, characterized in that L contains one or more branched moieties having the following structure wherein the terminal carbonyl group faces Ct or is covalently bonded to Ct.

26. The prodrug according to any one of claims 1 to 25, characterized in that L contains one, two, three, four or more linking moieties for initiators (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure Among them, the terminal amino group is covalently bonded to the initiator (F1, F2, F3, F4).

27. The prodrug according to claim 26, wherein, L comprises one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure wherein the terminal amino group is covalently bonded to the initiator (F1, F2, F3, F4), and B1s are independently selected from the group consisting of the following moieties 28. The prodrug according to claim 26, wherein, L comprises one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have structures selected from the following group wherein the terminal amino group is covalently bonded to the initiator (F1, F2, F3 or F4).

29. The prodrug according to claim 26, 27 or 28, wherein, the prodrug comprises an initiator F1.

30. The prodrug according to claim 29, wherein, L has the structure as claimed in claim 26, 27 or 28.

31. The prodrug according to any one of claims 1 to 25, wherein, L comprises one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure wherein the terminal amino group is covalently bonded to the initiator (F1, F2, F3, F4).

32. The prodrug according to claim 31, wherein, L comprises one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure wherein the terminal amino group is covalently bonded to the initiator (F1, F2, F3, F4).

33. The prodrug according to any one of claims 1 to 25, wherein, L comprises one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure Among them, the terminal amino group is covalently bonded to the initiator (F1, F2, F3, F4), and R 2 is a group of the second pharmacokinetic modulation moiety.

34. The prodrug according to claim 32, wherein, L comprises one, two, three, four or more linking moieties for the initiator (F1, F2, F3, F4), and the one, two, three, four or more linking moieties independently of one another have the following structure: Among them, the terminal amino group is covalently bonded to the initiator (F1, F2, F3, F4), and R 2 is a group of the second pharmacokinetic modulating moiety.

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