Camptothecin derivative and preparation method therefor and use thereof

Abstract

The present invention relates to the technical field of medicinal chemistry. Disclosed are a camptothecin derivative and a preparation method therefor and the use thereof. The derivative is a compound as shown in formula (I) and / or a pharmaceutically acceptable salt thereof, wherein R1 is selected from at least one of H, -NO2, -NH2, -OH and halogen; R2 is selected from at least one of H, acyl and substituted acyl; and R1 and R2 are not H at the same time. The method for preparing the camptothecin derivative comprises the following steps: performing a substitution reaction on a compound as shown in formula (II) and a reactant to obtain a compound as shown in formula (III), wherein the reactant is a reactant containing nitro and / or a reactant containing substituted acyl, Ra is nitro and hydrogen, and Rb is selected from at least one of acyl, substituted acyl and hydrogen. The camptothecin derivative has a higher tumor cell inhibitory activity and better safety.

Description

Camptothecin derivatives and their preparation methods and applications

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Chinese patent application 202410077258.5, filed on January 18, 2024, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to the technical field of medicinal chemistry, and in particular to a camptothecin derivative and a preparation method thereof, and application of the compound in the preparation of antibody-drug conjugates. Background Art

[0004] The primary function of DNA topoisomerase is to unwind DNA superhelices, promoting transcription and replication of DNA chains. Inhibiting topoisomerase activity leads to the accumulation of large amounts of broken DNA within tumor cells, inducing cell death. Topoisomerases are divided into topoisomerase I (Topo I) and topoisomerase II (Topo II). Camptothecin and its derivatives are important inhibitors of DNA topoisomerase I. Camptothecin derivatives such as irinotecan and topotecan are already clinically used to treat malignant tumors.

[0005] Camptothecin was first isolated from the plant Camptotheca acuminata (Davidia involucrata). It exhibits strong cytotoxicity and is effective against malignancies such as gastrointestinal tumors (gastric, colon, and rectal cancers), liver cancer, breast cancer, bladder cancer, and leukemia. However, its main drawbacks are its poor solubility and stability, high toxicity, and narrow safety window, limiting its clinical application.

[0006] Prodrugs are a medicinal chemistry technology that expands the therapeutic window. One type of prodrug is the antibody-drug conjugate (ADC). Through the high targeting and water solubility of antibodies and linkers to relevant antigens in tumor cells, the water solubility and therapeutic window of camptothecin derivatives can be simultaneously improved. If the linker is sufficiently stable, the ADC can become a sustained-release prodrug, also increasing the therapeutic window. ADC-conjugated prodrugs formed by conjugating the camptothecin derivatives Deruxtecan and SN38 to multiple antibodies have become high-quality solid tumor therapeutics.

[0007] Another type of prodrug is hypoxia-activated prodrugs (HAPs). Mitomycin C, a prodrug that relies on this activation mechanism, can be used to treat gastric and pancreatic cancers. Tumor tissues experience localized hypoxia due to differences in vascular structure and metabolism compared to normal tissues, a key mechanism by which tumors develop resistance to chemotherapy, immunotherapy, and radiotherapy. Hypoxia upregulates various reductases, such as nitroreductase, and this unique tumor environment can serve as a triggering mechanism for the specific activation of chemotherapeutic drugs. Radiotherapy often further upregulates reductases, making HAPs useful as radiosensitizers. As small molecule prodrugs, HAPs are more convenient to use than ADCs and can penetrate the blood-brain barrier to reach the central nervous system to treat brain tumors and brain metastases. HAPs and their active metabolites can be used as small molecule toxins in ADC molecules.

[0008] Camptothecin derivatives are known to have low cell proliferation inhibition activity and require a high dose-to-antibody ratio (DAR) as ADC toxins, which can easily cause ADC instability, resulting in higher production costs, greater synthesis difficulty and a lower safety window. Therefore, more active camptothecin derivatives are of great significance to the design and development of new ADCs. Summary of the Invention

[0009] The present invention aims to overcome the narrow safety window and low activity of camptothecin derivatives in the prior art, and to provide a camptothecin derivative, its preparation method, and its use. The camptothecin derivatives provided by the present invention have higher tumor cell inhibitory activity and better safety, and as ADC toxins, they have a larger safety window.

[0010] In order to achieve the above object, the present invention provides a camptothecin derivative in a first aspect, wherein the derivative is a compound represented by formula (I) and / or a pharmaceutically acceptable salt thereof:

[0011] Wherein, R1 is selected from at least one of H, -NO2, -NH2, -OH and halogen; R2 is selected from at least one of H, acyl and substituted acyl, and R1 and R2 are not H at the same time.

[0012] Preferably, the halogen is selected from at least one of F, Cl and Br.

[0013] Preferably, R1 is selected from at least one of H, -NO2 and -NH2, and R2 is hydrogen or a substituted acyl group.

[0014] Preferably, the substituted acyl group is at least one of a hydroxy substituted acyl group and / or an alkoxy substituted acyl group.

[0015] Preferably, the hydroxy-substituted acyl group is an α-hydroxy-substituted acyl group; further, it is an α-hydroxy-substituted acyl group containing a C1-C6 alkane, and more preferably, it is an α-hydroxyacetyl group; the alkoxy-substituted acyl group is an alkoxy-substituted acyl group containing a heterocycle and / or an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring, further preferably, it is an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring, and more preferably, it is a (1-methyl-2-nitro-1H-imidazol-5-yl)methoxyacyl group.

[0016] Preferably, the derivative is selected from:

[0017] At least one of .

[0018] Further preferably, the derivative is selected from:

[0019] At least one of .

[0020] A second aspect of the present invention provides a method for preparing a camptothecin derivative, the method comprising the following steps:

[0021] The compound represented by formula (II) and the reactant are subjected to a substitution reaction to obtain a compound represented by formula (III);

[0022] wherein the reactant is a reactant containing a nitro group and / or a reactant containing a substituted acyl group; Ra is a nitro group and hydrogen; Rb is at least one selected from an acyl group, a substituted acyl group and hydrogen, preferably a substituted acyl group and hydrogen, and Ra and Rb are not both H; or

[0023] (1) subjecting the compound represented by formula (II) and a reactant to a substitution reaction to obtain a compound represented by formula (III);

[0024] wherein the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, or a reactant containing a nitro group; Ra is a nitro group, and Rb is a substituted acyl group or hydrogen;

[0025] (2) subjecting the compound represented by formula (III) to a reduction reaction to obtain the compound represented by formula (IV); or

[0026] (1) subjecting the compound represented by formula (II) and a reactant to a substitution reaction to obtain a compound represented by formula (III);

[0027] wherein the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, or a reactant containing a nitro group; Ra is a nitro group, and Rb is a substituted acyl group or hydrogen;

[0028] (2) subjecting the compound represented by formula (III) to a reduction reaction to obtain the compound represented by formula (IV);

[0029] (3) subjecting the compound represented by formula (IV) to a Sandmeyer reaction; or

[0030] (1) subjecting the compound represented by formula (II) and a reactant to a substitution reaction to obtain a compound represented by formula (III);

[0031] wherein the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, or a reactant containing a nitro group; Ra is a nitro group, and Rb is a substituted acyl group or hydrogen;

[0032] (2) subjecting the compound represented by formula (III) to a reduction reaction to obtain the compound represented by formula (IV);

[0033] (3) subjecting the compound represented by formula (IV) to a Buchwald-Hartwig coupling reaction;

[0034] Preferably, before the substitution reaction, the compound represented by formula (II) is reacted with an amino protecting agent.

[0035] Further preferably, the amino protecting agent is at least one selected from benzyl chloroformate, di-tert-butyl dicarbonate and 9-fluorenylmethyl chloroformate.

[0036] Preferably, the reactant containing a nitro group is nitric acid.

[0037] Preferably, the substituted acyl group is a hydroxy substituted acyl group and / or an alkoxy substituted acyl group.

[0038] Preferably, the hydroxy-substituted acyl group is an α-hydroxy-substituted acyl group; further, it is an α-hydroxy-substituted acyl group containing a C1-C6 alkane, and more preferably, it is an α-hydroxyacetyl group; the alkoxy-substituted acyl group is an alkoxy-substituted acyl group containing a heterocycle and / or an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring, and further preferably, it is an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring.

[0039] More preferably, the reactant containing a substituted acyl group is selected from 2-hydroxyacetic acid, phenyl chloroformate and (1-methyl-2-nitro-1H-imidazol-5-yl)methyl chloroformate.

[0040] Preferably, in step (2), the reduction reaction comprises contacting the compound represented by formula (III) with a reducing agent.

[0041] More preferably, the reducing agent is tetrahydroxydiboron and / or sodium borohydride.

[0042] Preferably, when the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, the substitution reaction comprises:

[0043] The compound represented by formula (II) is subjected to a substitution reaction with a reactant containing a nitro group to obtain a compound represented by formula (V); the compound represented by formula (V) is then subjected to a substitution reaction with a reactant containing a substituted acyl group;

[0044] Further preferably, when the reactant contains a nitro group, the conditions of the substitution reaction at least meet the following requirements: inert gas protection, temperature of -4-0°C, and time of 50-70 min.

[0045] When the reactant contains a substituted acyl group, the conditions of the substitution reaction at least meet the following requirements: protection by inert gas, temperature of 25-30° C., and time of 120-130 min.

[0046] The reduction reaction conditions at least meet the following requirements: inert gas protection, temperature of 20-25° C., and time of 4-10 min.

[0047] The third aspect of the present invention provides the use of the derivatives described in the first aspect and the derivatives prepared by the method described in the second aspect in the preparation of anti-tumor drugs.

[0048] Preferably, the anti-tumor drug is an antibody-drug conjugate.

[0049] Preferably, the anti-tumor drug is a hypoxia-activated prodrug.

[0050] Preferably, the anti-tumor drug is a small molecule active drug.

[0051] Further preferably, the tumor is selected from at least one of colon cancer, gastric cancer, breast cancer and lung cancer.

[0052] Further preferably, the tumor is an in situ lesion and / or a metastatic lesion.

[0053] Further preferably, the tumor is selected as a central tumor and / or a central metastatic lesion.

[0054] The fourth aspect of the present invention provides an antibody-drug conjugate, in which the derivative described in the first aspect and / or the derivative prepared by the method described in the second aspect is connected to the antibody via a linker and / or is directly coupled to the antibody.

[0055] Through the above technical solution, the camptothecin derivatives provided by the present invention have high tumor cell inhibitory activity and great clinical value. As ADC toxins, they can further expand the safety window of ADC drugs. Furthermore, as prodrugs, they exhibit a significant difference in activity before and after activation. Before activation, they do not harm normal tissues, but only exert their activity after activation in tumor tissues, resulting in higher tumor cell inhibitory activity and improved safety.

[0056] Preferably, a prodrug of a camptothecin derivative activated by nitroreductase has low activity, does not harm normal tissues before activation, and only becomes highly active after activation in tumor tissue. Camptothecin derivatives with a significant difference in activity before and after activation have great clinical value. By introducing water-soluble groups or preparing prodrugs, camptothecin derivatives can simultaneously improve their therapeutic window and solubility, thereby enhancing their drugability. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0058] FIG1 is a hydrogen spectrum of compound 1 prepared in Example 1 of the present invention;

[0059] FIG2 is a hydrogen spectrum of compound 2 prepared in Example 2 of the present invention;

[0060] FIG3 is a hydrogen spectrum of compound 3 prepared in Example 3 of the present invention;

[0061] FIG4 is a hydrogen spectrum of compound 4 obtained in Example 4 of the present invention;

[0062] FIG5 is a hydrogen spectrum of compound 5 obtained in Example 5 of the present invention;

[0063] FIG6 is a comparison chart of weight changes of mice in Test Example 2 of the present invention;

[0064] FIG7 is a comparison diagram of tumor volume changes in Test Example 2 of the present invention. DETAILED DESCRIPTION

[0065] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0066] In a first aspect, the present invention provides a camptothecin derivative, wherein the derivative is a compound represented by formula (I) and / or a pharmaceutically acceptable salt thereof:

[0067] Wherein, R1 is selected from at least one of H, -NO2, -NH2, -OH and halogen; R2 is selected from at least one of H, acyl and substituted acyl, and R1 and R2 are not H at the same time.

[0068] During the research process of camptothecin derivatives, the inventors found that camptothecin derivatives having the structure of formula (I) have higher cancer cell inhibitory activity and better safety, can inhibit the growth of tumor cells, and have a larger safety window as ADC toxins.

[0069] According to the present invention, "acceptable" means that a formulation component or active ingredient has no undue adverse effect on health and well-being for the general purpose of treatment.

[0070] According to the present invention, "pharmaceutically acceptable" refers to a substance, such as a carrier or diluent, that does not abrogate the biological activity or properties of the compound and is relatively non-toxic, i.e., a substance that does not cause undesirable biological effects or interact in a deleterious manner with any of its components when administered to a subject.

[0071] According to the present invention, "pharmaceutically acceptable salt" refers to a form of a compound that does not cause significant irritation to the organism to which it is administered and does not abrogate the biological activity and properties of the compound. In certain specific aspects, the pharmaceutically acceptable salt is obtained by reacting the compound represented by formula (I) with an acid, such as an inorganic acid such as hydrochloric acid, hydrobromic acid, hydrofluoric acid, sulfuric acid, phosphoric acid, nitric acid, phosphoric acid; an organic acid such as formic acid, acetic acid, propionic acid, oxalic acid, trifluoroacetic acid, malonic acid, succinic acid, fumaric acid, maleic acid, lactic acid, malic acid, tartaric acid, citric acid, picric acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid; and an acidic amino acid such as aspartic acid and glutamic acid.

[0072] According to the present invention, the compound represented by formula (I) and its pharmaceutically acceptable salt can be prepared into various preparations, which contain a safe and effective amount of the compound of the present invention or its pharmaceutically acceptable salt and a pharmacologically acceptable excipient or carrier.

[0073] According to the present invention, pharmaceutically acceptable salts also include corresponding solvent addition forms or crystal forms, in particular solvates or multiple crystal forms. Solvates contain stoichiometric or non-stoichiometric amounts of solvent and are selectively formed during crystallization with pharmaceutically acceptable solvents such as water, ethanol, etc. When the solvent during crystallization is water, hydrates are formed, or when the solvent is ethanol, alcoholates are formed. Solvates of the compounds represented by formula (I) can be conveniently prepared or formed into corresponding solvates according to the methods described herein.

[0074] According to the present invention, the hydrate of the solvate of the compound shown in formula (I) is obtained by recrystallization from a mixed solvent of water / organic solvent, and the organic solvent used includes, but is not limited to, tetrahydrofuran, acetone, ethanol or methanol. In addition, the compound mentioned here can exist in non-solvated and solvated forms. In short, for the compound and preparation method provided by the present invention, the solvated form is considered to be equivalent to the non-solvated form.

[0075] According to the present invention, the compound shown in formula (I) can be prepared into different forms, including but not limited to, amorphous, powder and nanoparticle forms. In addition, the compound shown in formula (I) can be a single crystal form or a polymorph. Polymorphs include different lattice arrangements of the same elements of the compound. Polymorphs usually have different X-ray diffraction spectra, infrared spectra, melting points, density, hardness, crystal form, optical and electrical properties, stability and solubility. Different influencing factors include recrystallization solvent, crystallization rate and storage temperature, which may cause a single crystal form to be the dominant polymorphic compound.

[0076] According to the present invention, the compound shown in formula (I) may have chiral centers and / or chiral axes, and therefore appear in the form of racemates, racemic mixtures, single enantiomers, diastereomeric compounds and single diastereomers and cis-trans isomers. Each chiral center or chiral axis will independently produce two optical isomers, and all possible optical isomers and diastereomeric mixtures as well as pure or partially purified compounds are included in the protection scope of the present invention. The compound shown in formula (I) disclosed in the present invention includes all isomeric forms corresponding to the compound.

[0077] According to the present invention, the compound may contain unnatural proportions of atomic isotopes on one or more of the atoms that constitute the compound. For example, the compound may be labeled with a radioactive isotope, such as deuterium ( 2 H)), tritium ( 3 H) and C-14( 14 C). For example, deuterated compounds can be formed by replacing hydrogen atoms with heavy hydrogen. The bond between deuterium and carbon is stronger than that between ordinary hydrogen and carbon. Compared to non-deuterated drugs, deuterated drugs generally have advantages such as reduced toxic side effects, increased drug stability, enhanced efficacy, and prolonged drug half-life in vivo. All isotopic variations of the compounds of this invention, whether radioactive or not, are encompassed by this invention. In this invention, unless otherwise specified, the use of "or" or "and" means "and / or."

[0078] According to the present invention, the halogen is selected from at least one of F, Cl and Br; the inventors found that when R1 is F, Cl and Br, the corresponding compound has anti-tumor activity.

[0079] According to the present invention, when R1 is selected from at least one of H, -NO2, and -NH2, and R2 is hydrogen or a substituted acyl group, the corresponding compounds all exhibit excellent anti-tumor activity. During their research, the inventors unexpectedly discovered that camptothecin derivatives containing a nitro group have low prodrug activity, but amino-containing camptothecin derivatives activated by nitroreductase have higher activity. Camptothecin derivatives with a significant difference in activity before and after activation have great clinical value. Camptothecin derivatives exhibited excellent activity when the substituted acyl group was at least one of a hydroxy-substituted acyl group and / or an alkoxy-substituted acyl group.

[0080] According to the present invention, when the hydroxy-substituted acyl group is an α-hydroxy-substituted acyl group, the derivative side chain contains an -OH group that is easy to connect, and at the same time has good cellular activity, making it suitable as a small molecule toxin for ADC. Further preferably, when the α-hydroxy-substituted acyl group is an α-hydroxy-substituted acyl group containing a C1-C6 alkane, at least one of an α-hydroxy-substituted acyl group containing a C1-C6 straight-chain alkane, an α-hydroxy-substituted acyl group containing a C1-C6 branched-chain alkane, and an α-hydroxy-substituted acyl group containing a cycloalkyl group can be used. The α-hydroxyl group containing a C1-C6 straight-chain alkane, a C1-C6 branched-chain alkane, or a cycloalkyl group can retain the tumor cell inhibitory activity of the camptothecin derivative while optimizing the drugability and inhibitory activity of the camptothecin derivative; more preferably, when the α-hydroxy-substituted acyl group is an α-hydroxyacetyl group, the camptothecin derivative has higher tumor cell inhibitory activity and better safety, and has a larger safety window as an ADC toxin.

[0081] According to the present invention, the alkoxy-substituted acyl group is an alkoxy-substituted acyl group containing a heterocycle and / or an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring. During research, the inventors discovered that when the alkoxy-substituted acyl group is an alkoxy-substituted acyl group containing a heterocycle and / or an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring, the alkoxy-substituted acyl group can self-eliminate under the action of a reductase to produce a camptothecin derivative with better tumor cell inhibition activity. Further preferably, the alkoxy-substituted acyl group is an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring. The inventors discovered that after the nitro group of the imidazole ring enters tumor tissue, it is reduced to an amine group under the catalysis of nitroreductase to form an unstable intermediate, which then undergoes a self-elimination reaction to produce a more active metabolite with better prodrug properties and better tumor cell inhibition activity. More preferably, the camptothecin derivative in which the alkoxy-substituted acyl group is (1-methyl-2-nitro-1H-imidazol-5-yl)methoxyacyl generates a more active metabolite, exitecan, through a self-elimination reaction, has better prodrug properties and better safety, and has a larger safety window as an ADC toxin.

[0082] According to the present invention, "halogen" (or halo) refers to fluorine, chlorine, bromine or iodine. The term "halo" (or "halogen substituted") appearing before the group name indicates that the group is partially or fully halogenated, that is, substituted by F, Cl, Br or I in any combination, preferably substituted by F or Cl.

[0083] According to the present invention, "cycloalkyl" refers to a non-aromatic hydrocarbon ring system (monocyclic, bicyclic or polycyclic). If the carbocyclic ring contains at least one double bond, the partially unsaturated cycloalkyl group may be referred to as a "cycloalkenyl group", or if the carbocyclic ring contains at least one triple bond, the partially unsaturated cycloalkyl group may be referred to as a "cycloalkynyl group". Cycloalkyl groups may include monocyclic or polycyclic (e.g., having 2, 3, or 4 fused rings) groups and spirocycles. In some embodiments, the cycloalkyl group is monocyclic. In some embodiments, the cycloalkyl group is monocyclic or bicyclic. The ring-forming carbon atoms of the cycloalkyl group may optionally be oxidized to form an oxo or sulfide group. Cycloalkyl groups also include cycloalkylene groups. In some embodiments, the cycloalkyl group contains 0, 1, or 2 double bonds. In some embodiments, the cycloalkyl group contains 1 or 2 double bonds (partially unsaturated cycloalkyl groups). In some embodiments, the cycloalkyl group may be fused with an aryl group, a heteroaryl group, a cycloalkyl group, and a heterocycloalkyl group. In some embodiments, the cycloalkyl group may be fused with an aryl group, a cycloalkyl group, and a heterocycloalkyl group. In some embodiments, cycloalkyl groups can be fused with aryl groups and heterocycloalkyl groups. In some embodiments, cycloalkyl groups can be fused with aryl groups and cycloalkyl groups. Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclopentenyl, cyclohexenyl, cyclohexadienyl, cycloheptatrienyl, norbornyl, norpinyl, norcaryl, bicyclo[1.1.1]pentanyl, bicyclo[2.1.1]hexanyl, and the like.

[0084] According to the present invention, "heterocycloalkyl" refers to a non-aromatic ring or ring system, which may optionally contain one or more alkenylene groups as part of the ring structure, which has at least one heteroatom ring member independently selected from boron, phosphorus, nitrogen, sulfur, oxygen and phosphorus. If the heterocycloalkyl contains at least one double bond, the partially unsaturated heterocycloalkyl may be referred to as a "heterocycloalkenyl", or if the heterocycloalkyl contains at least one triple bond, the partially unsaturated heterocycloalkyl may be referred to as a "heterocycloalkynyl". The heterocycloalkyl may include a monocyclic, bicyclic, spirocyclic or polycyclic (e.g., having two fused or bridged rings) ring system. In certain embodiments, the heterocycloalkyl is a monocyclic group having 1, 2 or 3 heteroatoms independently selected from nitrogen, sulfur and oxygen. The ring-forming carbon atoms and heteroatoms of the heterocycloalkyl may be optionally oxidized to form oxo or sulfide groups or other oxidized bonds (e.g., C(O), S(O), C(S) or S(O) 2, N-oxides, etc.), or the nitrogen atom may be quaternized. The heterocycloalkyl may be connected via ring-forming carbon atoms or ring-forming heteroatoms. In some embodiments, heterocycloalkyl contains 0 to 3 double bonds. In some embodiments, heterocycloalkyl contains 0 to 2 double bonds. The definition of heterocycloalkyl also includes parts with one or more aromatic rings fused to the heterocycloalkyl ring (i.e., sharing a key with it), such as benzo derivatives of piperidine, morpholine, azacycloheptatriene or thienyl. The heterocycloalkyl containing fused aromatic rings can be connected via any ring-forming atoms, including the ring-forming atoms of the fused aromatic ring. Examples of heterocycloalkyl groups include, but are not limited to, azetidinyl, azepanyl, dihydrobenzofuranyl, dihydrofuranyl, dihydropyranyl, N-morpholinyl, 3-oxa-9-azaspiro[5.5]undecyl, 1-oxa-8-azaspiro[4.5]decyl, piperidinyl, piperazinyl, oxopiperazinyl, pyranyl, pyrrolidinyl, quinuclyl, tetrahydrofuranyl, tetrahydropyranyl, 1,2,3,4-tetrahydroquinolinyl, tropanediyl, 4,5,6,7-tetrahydrothiazolo[5,4-c]pyridinyl, 4,5,6,7-tetrahydro-1H-imidazole and [4,5-c]pyridine, N-methylpiperidinyl, tetrahydroimidazolyl, pyrazolidinyl, butyrolactam, valerolactam, imidazolinone, hydantoin, dioxolane, phthalimide, pyrimidine-2,4(1H,3H)-dione, 1,4-dioxane, morpholinyl, thiomorpholinyl, thiomorpholine-S-oxide, thiomorpholine-S,S-oxide, piperazinyl, pyranyl, pyridone, 3-pyrrolinyl, thiopyranyl, pyrone, tetrahydrothiophenyl, 2-azaspiro[3.3]heptanyl, indolinyl, and the like.

[0085] According to the present invention, "alkoxy" refers to an alkyl group bonded to the rest of the molecule via an ether oxygen atom. Representative alkoxy groups are those having 1 to 6 carbon atoms, such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, and tert-butoxy. As used herein, "alkoxy" includes unsubstituted and substituted alkoxy groups, especially those substituted with one or more halogens. Preferred alkoxy groups are selected from -OCH, -OCF, -CHF2O, -CF3CH2O, -i-PrO, -n-PrO, -i-BuO, -n-BuO, or -t-BuO.

[0086] According to the present invention, the derivative is selected from:

[0087] The inventors have discovered that the compound having the above-mentioned stereo configuration has tumor cell inhibitory activity.

[0088] Preferably, the derivative is selected from:

[0089] When at least one of the above is present, it has higher tumor cell inhibitory activity and has great clinical value. As an ADC toxin, it can further expand the safety window of ADC drugs.

[0090] According to the present invention, a wedge-shaped solid key is used. and dotted wedge key To indicate the absolute configuration of a stereocenter, use a straight solid bond and straight dashed key Indicate the relative configuration of stereocenters with a wavy line Indicates a wedge-shaped solid key or dotted wedge key Or use a wavy line Indicates a straight solid bond or straight dashed key Unless otherwise stated, Indicates a single bond or a double bond.

[0091] In a second aspect, the present invention provides a method for preparing a camptothecin derivative, the method comprising the following steps:

[0092] The compound represented by formula (II) and the reactant are subjected to a substitution reaction to obtain a compound represented by formula (III);

[0093] wherein the reactant is a reactant containing a nitro group and / or a reactant containing a substituted acyl group; Ra is a nitro group and hydrogen; Rb is at least one selected from an acyl group, a substituted acyl group and hydrogen, preferably a substituted acyl group and hydrogen, and Ra and Rb are not both H; or

[0094] (1) subjecting the compound represented by formula (II) and a reactant to a substitution reaction to obtain a compound represented by formula (III);

[0095] wherein the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, or a reactant containing a nitro group; Ra is a nitro group, and Rb is a substituted acyl group or hydrogen;

[0096] (2) subjecting the compound represented by formula (III) to a reduction reaction to obtain the compound represented by formula (IV); or

[0097] (1) subjecting the compound represented by formula (II) and a reactant to a substitution reaction to obtain a compound represented by formula (III);

[0098] wherein the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, or a reactant containing a nitro group; Ra is a nitro group, and Rb is a substituted acyl group or hydrogen;

[0099] (2) subjecting the compound represented by formula (III) to a reduction reaction to obtain the compound represented by formula (IV);

[0100] (3) subjecting the compound represented by formula (IV) to a Sandmeyer reaction; or

[0101] (1) subjecting the compound represented by formula (II) and a reactant to a substitution reaction to obtain a compound represented by formula (III);

[0102] wherein the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, or a reactant containing a nitro group; Ra is a nitro group, and Rb is a substituted acyl group or hydrogen;

[0103] (2) subjecting the compound represented by formula (III) to a reduction reaction to obtain the compound represented by formula (IV);

[0104] (3) subjecting the compound represented by formula (IV) to a Buchwald-Hartwig coupling reaction;

[0105] The compound represented by formula (I) can be prepared by the above-mentioned preparation method. The compound has high tumor cell inhibitory activity and great clinical value. As an ADC toxin, it can further expand the safety window of ADC drugs. Moreover, the preparation process is simple and easy to operate.

[0106] According to the present invention, before the substitution reaction, the compound represented by formula (II) is reacted with an amino protecting agent; after the amino group is protected, the amino group in the compound represented by formula (II) can be prevented from being substituted during the substitution process. Preferably, the amino protecting agent is selected from at least one of benzyl chloroformate, di-tert-butyl dicarbonate and 9-fluorenylmethyl chloroformate, and the corresponding amino protecting agent can be selected according to the substituent group and the reaction conditions. The amino protecting agent can also adopt other derivatives of the same type of benzyloxycarbonyl, tert-butyloxycarbonyl and fluorenylmethyloxycarbonyl, or other amino protecting agents with the same effect, such as methoxycarbonyl, allyloxycarbonyl or trityl derivatives, according to different reaction conditions. The inventors have found that methoxycarbonyl chloride can also be used to introduce methoxycarbonyl, allyl chloroformate to introduce allyloxycarbonyl, or trityl ether to introduce trityl to protect the amino group. The above-mentioned amino protecting agent can be deprotected by catalytic hydrogenolysis, acidolysis cleavage, Na / NH3 (liquid) reduction, Lewis acid and other conditions according to different protecting groups. After the substitution reaction is completed, the amino protecting agent can be deprotected according to the removal conditions, and then the corresponding substituent group can be introduced on the amino group. Alternatively, the compound represented by formula (II) can be subjected to a substitution reaction with the reactant first, and then the other group introduction reaction can be carried out. If the compound has a reactive group that competes with the later introduced group, the corresponding protecting agent can be selected to protect it before the substitution reaction.

[0107] According to the present invention, the reactant containing a nitro group is nitric acid; the nitric acid can be used alone or in combination with other reagents, and pure nitric acid, fuming nitric acid, and concentrated nitric acid can be used as the reactant for the nitro group; concentrated nitric acid or a mixture of fuming nitric acid and concentrated sulfuric acid in a certain ratio can also be used as the reactant for the nitro group, and the ratio can be 1:3-6, or a mixing ratio well known to those skilled in the art; a nitric acid-acetic anhydride solution can also be used as the reactant for the nitro group, and the volume ratio of nitric acid to acetic anhydride is 1:50-70.

[0108] According to the present invention, when the hydroxy-substituted acyl group is an α-hydroxy-substituted acyl group, the derivative side chain contains an -OH group that is easy to connect, and at the same time has good cellular activity, making it suitable as a small molecule toxin for ADC. Further preferably, when the α-hydroxy-substituted acyl group is an α-hydroxy-substituted acyl group containing a C1-C6 alkane, at least one of an α-hydroxy-substituted acyl group containing a C1-C6 straight-chain alkane, an α-hydroxy-substituted acyl group containing a C1-C6 branched-chain alkane, and an α-hydroxy-substituted acyl group containing a cycloalkyl group can be used. The α-hydroxy group containing a C1-C6 straight-chain alkane, a C1-C6 branched-chain alkane, or a cycloalkyl group can retain the tumor cell inhibitory activity of the camptothecin derivative while optimizing the drugability and inhibitory activity of the camptothecin derivative. The alkoxy-substituted acyl group is an alkoxy-substituted acyl group containing a heterocycle and / or an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring. During research, the inventors discovered that when the alkoxy-substituted acyl group is an alkoxy-substituted acyl group containing a heterocycle and / or an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring, the alkoxy-substituted acyl group can be self-eliminated under the action of a reductase to produce a camptothecin derivative with better tumor cell inhibitory activity. More preferably, when the reactant containing the substituted acyl group is selected from 2-hydroxyacetic acid, phenylchloroformate, and (1-methyl-2-nitro-1H-imidazol-5-yl)methyl chloroformate, the synthetic route is short, the reaction conditions are simple, and the operation is easy. The synthesized compound has higher tumor cell inhibitory activity and better safety, and has a larger safety window as an ADC toxin.

[0109] According to the present invention, in step (2), the reduction reaction comprises contacting the compound represented by formula (III) with a reducing agent; the reducing agent may be tetrahydroxydiboron, sodium borohydride, lithium aluminum tetrahydride or hydrogen gas alone, or different reducing agents may be selected according to the substituent groups. Catalysts such as 4,4'-bipyridine, Raney nickel (Raney Ni), palladium carbon, platinum carbon, etc. may also be added to the reduction reaction system to shorten the reaction process. Preferably, when the reducing agent is tetrahydroxydiboron and / or sodium borohydride, the reduction effect is better. When the reducing agent is tetrahydroxydiboron, 4,4'-bipyridine may be added as a catalyst to shorten the reduction reaction time.

[0110] According to the present invention, when the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, the substitution reaction comprises:

[0111] The compound represented by formula (II) is subjected to a substitution reaction with a reactant containing a nitro group to obtain a compound represented by formula (V); the compound represented by formula (V) is then subjected to a substitution reaction with a reactant containing a substituted acyl group;

[0112] The inventors have found that the above-mentioned substitution step can improve the yield, reduce the generation of by-products, and the reaction conditions are mild and easy to operate.

[0113] According to the present invention, when the reactant is a reactant containing a nitro group, the conditions of the substitution reaction at least meet the following requirements: inert gas protection, the inert gas is selected from xenon, argon or nitrogen, the temperature is -4-0°C, specifically -4°C, -3°C, -2°C, -1°C, 0°C, or any value between the above two values, the time is 50-70min, specifically 50min, 55min, 60min, 65min, 70min, or any value between the above two values;

[0114] When the reactant is a reactant containing a substituted acyl group, the conditions of the substitution reaction at least meet the following requirements: inert gas protection, the inert gas is selected from xenon, argon or nitrogen, the temperature is 25-30°C, specifically 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, or any value between the above two values, and the time is 120-130 min, specifically 120 min, 121 min, 122 min, 123 min, 124 min, 125 min, 126 min, 127 min, 128 min, 129 min, 130 min, or any value between the above two values;

[0115] The conditions for the reduction reaction at least meet the following requirements: inert gas protection, the inert gas is selected from xenon, argon or nitrogen, the temperature is 20-25°C, specifically 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, or any value between the above two values, and the time is 4-10 min, specifically 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, or any value between the above two values.

[0116] The reaction solvent used in the above preparation method can be ethyl acetate (EA), dimethylformamide (DMF), dichloromethane (DCM), and 1,2-dichloroethane (DCE), or a reaction solvent known to those skilled in the art. After the above reaction is completed, the target compound is obtained by post-treatment. The post-treatment process includes quenching, extraction, washing, and purification. For the quenching reaction, water can be used as a quenching agent in an amount of about 100-500 mL, which can be appropriately increased or decreased according to the amount of the reactants. For extraction, methanol, acetonitrile, tetrahydrofuran, ethyl acetate, dichloromethane, etc. can be used. The amount of the extractant is about 300-500 mL, which can be appropriately increased or decreased according to the amount of the reactants. The extractant can be washed with saturated salt water, saturated sodium carbonate aqueous solution, saturated sodium bicarbonate aqueous solution, etc. After washing, it can be dried with anhydrous sodium sulfate or anhydrous magnesium sulfate. Before purification, it is first concentrated under reduced pressure to obtain a small amount of crude product solution, which is then purified on a silica gel column, or directly purified by preparative liquid chromatography (pre-HPLC). In addition to the main reactants and reaction solvent, catalysts and reaction aids can be added to the reaction system to accelerate the reaction process and reduce the production of by-products. Catalysts and reaction aids can be palladium on carbon (Pd / C), 4,4'-bipyridine, triethylamine (TEA or Et3N), N,N-diisopropylethylamine (DIEA), and 2-(7-azobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU). During the reaction, a small amount of reactants can be withdrawn with a syringe for thin-layer chromatography (TLC) analysis or liquid chromatography-mass spectrometry (LC-MS) analysis. After confirming the completion of the reaction, the reaction is quenched.

[0117] As a specific embodiment of the present invention, a specific method for introducing a halogen substituent is to convert an amine group to a halogen through the Sandmeyer reaction. Specifically, the corresponding benzonitrile is obtained under the action of CuCN, which is then treated with CuCl or CuBr to obtain the corresponding halogenated derivative. Alternatively, the iodinated derivative is heated with sodium iodide, which is then treated with silver tetrafluoroborate to obtain a diazonium fluoroborate, which is then heated to obtain a fluorinated derivative.

[0118] As a specific embodiment of the present invention, a specific method for introducing a hydroxyl substituent is as follows: a halogen-substituted compound is reacted with an amino compound via a Buchwald-Hartwig coupling reaction to obtain a substituted amino compound, followed by deprotection and acidification with hydrochloric acid to obtain a hydroxyl-substituted compound wherein R is a hydroxyl group. Alternatively, a hydroxyl-substituted compound wherein R is a hydroxyl group is obtained by mixing the amino compound with nitrous acid and subjecting it to a Sandmeyer reaction.

[0119] In addition to the above-mentioned preparation methods, the compounds can also be synthesized by combining the known techniques disclosed in the prior art with the methods disclosed in the present invention. In addition, the solvents, temperatures and other reaction conditions mentioned herein can be changed according to different reactants. The starting materials used for the synthesis of camptothecin derivatives can be synthesized or commercially available. The compounds of the present invention and other related compounds with different substituents can be synthesized using known techniques and raw materials. The general method for preparing compounds can be changed by using appropriate reagents and the conditions for introducing different groups into the molecular formula provided herein.

[0120] For example, the compound represented by formula (I) can be prepared by the methods of general reaction schemes 1-3.

[0121] The general reaction scheme 1 is as follows:

[0122] Using exitecan (compound 1A) as a starting material, the amino group is protected by an amino protecting agent, di-tert-butyl dicarbonate ((Boc)2O) to obtain compound 1B, which is then subjected to a substitution reaction with a reactant containing a nitro group, using a mixed acid of nitric acid (HNO3) and acetic anhydride (Ac2O) as the reactant containing a nitro group to obtain compound 1C; after the substitution reaction with the reactant containing a nitro group is completed, the Boc protecting group of the amino group of compound 1C is removed by trifluoroacetic acid (TFA) to obtain compound 1; compound 1 is subjected to a substitution reaction with a reactant containing a substituted acyl group, using 2-hydroxyacetic acid as the reactant containing a substituted acyl group to obtain compound 2; compound 2 is contacted with a reducing agent, using tetrahydroxydiboron as the reducing agent to obtain compound 3;

[0123] The general reaction scheme 2 is as follows:

[0124] Compound 1C is directly contacted with a reducing agent, tetrahydroxydiboron, to obtain compound 1D, and the Boc protecting group of the amino group of compound 1D is removed by trifluoroacetic acid (TFA) to obtain compound 4;

[0125] The general reaction scheme 3 is as follows:

[0126] Using exitecan (compound 1A) as the starting material, compound 1F was obtained by reaction with phenyl chloroformate, and then coupled with (1-methyl-2-nitro-1H-imidazol-5-yl)methanol to obtain compound 5.

[0127] After the nitro group of imidazole in compound 5 enters the tumor tissue, it is reduced to an amine group under the catalysis of nitroreductase to form an unstable intermediate 5A, which then generates the active substance ixetem (compound 1A) through a self-elimination reaction;

[0128] After entering the tumor tissue, the 8-nitro group in compound 2 is reduced to an amine group under the catalysis of nitroreductase, generating the active substance compound 3;

[0129] After entering the tumor tissue, the 8-nitro group in compound 1 is reduced to an amine group under the catalysis of nitroreductase, generating the active substance compound 4;

[0130] According to the present invention, although the numerical ranges and parameters used to define the broader scope of the invention are approximate, the numerical values ​​in the specific examples are presented herein as precisely as possible. However, any numerical value inherently and inevitably contains standard deviations due to individual testing methods. As used herein, "about" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a particular value or range. Alternatively, the term "about" means that the actual value falls within an acceptable standard error of the mean, as determined by one skilled in the art. Except in the experimental examples, or unless otherwise expressly indicated, all ranges, amounts, values, and percentages used herein (e.g., to describe material amounts, time periods, temperatures, operating conditions, quantitative ratios, and the like) are to be understood as modified by the word "about." Therefore, unless otherwise indicated, the numerical parameters disclosed in this specification and the appended claims are approximate and may be modified as needed. At a minimum, these numerical parameters should be understood to include the number of significant digits indicated and to use normal rounding.

[0131] In a third aspect, the present invention provides the use of the derivatives described in the first aspect and the derivatives prepared by the method described in the second aspect in the preparation of anti-tumor drugs; the anti-tumor drugs may be chemical drugs using the camptothecin derivatives as active ingredients, or antibody-drug conjugates using the camptothecin derivatives as small molecule toxins; preferably, the anti-tumor drugs are more effective when they are antibody-drug conjugates, wherein the antibodies may be monoclonal antibodies, bispecific antibodies, or nanoantibodies, specifically targeting HER2, HER3, CD25, CD30, and c-MET, or currently available antibodies. The camptothecin derivatives may also be used as sensitizers for adjuvant radiotherapy.

[0132] According to the present invention, the anti-tumor drug is preferably a hypoxia-activated prodrug (HAP); further preferably, the anti-tumor drug is a small molecule active drug. Hypoxia-activated prodrugs are drugs that can be activated and release drug molecules in a hypoxic environment. These drugs are stable under normoxic conditions but can be activated through a single-electron reduction process in hypoxic environments, thereby exerting their cytotoxic effects. The main feature of hypoxia-activated prodrugs is that they only kill tumor cells in hypoxic environments, thereby reducing side effects on normal tissues. The compounds of the present invention can be administered orally, rectally, parenterally (intravenously, intramuscularly, or subcutaneously), or topically. Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In these solid dosage forms, the active compound is mixed with at least one conventional inert excipient (or carrier), such as sodium citrate or dicalcium phosphate, or with the following ingredients: (a) fillers or extenders, for example, starches, lactose, sucrose, glucose, mannitol, and silicic acid; (b) binders, for example, hydroxymethylcellulose, alginates, gelatin, polyvinyl pyrrolidone, sucrose, and acacia; (c) humectants, for example, glycerol; (d) disintegrants, for example, agar, calcium carbonate, potato or tapioca starch, alginic acid, certain complex silicates, and sodium carbonate; (e) solubilizers, for example, paraffin; (f) absorption accelerators, for example, quaternary ammonium compounds; (g) wetting agents, for example, cetyl alcohol and glyceryl monostearate; (h) adsorbents, for example, kaolin; and (i) lubricants, for example, talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, or mixtures thereof. In the case of capsules, tablets and pills, the dosage forms may also comprise buffering agents.

[0133] According to the present invention, solid dosage forms such as tablets, drupes, capsules, pills, and granules can be prepared using coatings and shell materials, such as enteric coatings and other materials known in the art. They can contain opacifying agents, and the release of the active compound or compounds in such compositions can be delayed in a certain portion of the digestive tract. Examples of embedding components that can be used are polymeric substances and waxes. If desired, the active compound can also be microencapsulated with one or more of the above-mentioned excipients.

[0134] According to the present invention, liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, solutions, suspensions, syrups or tinctures. In addition to the active compound, the liquid dosage form may contain an inert diluent conventionally used in the art, such as water or other solvents, solubilizers and emulsifiers, for example, ethanol, isopropyl alcohol, ethyl carbonate, ethyl acetate, propylene glycol, 1,3-butylene glycol, dimethylformamide and oils, in particular cottonseed oil, peanut oil, corn germ oil, olive oil, castor oil and sesame oil or mixtures thereof.

[0135] According to the present invention, in addition to these inert diluents, the composition may also contain adjuvants such as wetting agents, emulsifying and suspending agents, sweetening agents, flavoring agents, and perfumes.

[0136] According to the invention, suspensions may contain, in addition to the active compounds, suspending agents such as, for example, ethoxylated isostearyl alcohol, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum methoxide and agar, or mixtures of these substances.

[0137] According to the present invention, the composition for parenteral injection can comprise physiologically acceptable sterile aqueous or anhydrous solutions, dispersions, suspensions or emulsions, and sterile powders for reconstitution into sterile injectable solutions or dispersions. Suitable aqueous and non-aqueous carriers, diluents, solvents or excipients include water, ethanol, polyols and suitable mixtures thereof.

[0138] According to the present invention, the dosage form of the compound of this invention for topical administration includes ointment, powder, patch, spray and inhalant.The active ingredient is mixed under sterile conditions with a physiologically acceptable carrier and any preservatives, buffers, or propellants that may be needed if necessary.

[0139] According to the present invention, the compound can be administered alone or in combination with other pharmaceutically acceptable compounds or physical therapies such as radiotherapy, photodynamic therapy, and ablation therapy. When using a pharmaceutical composition, a safe and effective amount of the compound of the present invention is applied to a mammal (such as a human) in need of treatment, wherein the dosage during administration is a pharmaceutically effective dosage. For a person weighing 60 kg, the daily dosage is generally 1-2000 mg, preferably 50-1000 mg. Of course, the specific dosage should also take into account factors such as the route of administration and the patient's health status, which are all within the skill of a skilled physician.

[0140] According to the present invention, the terms "treat," "treatment," or "therapy" as used herein include alleviating, inhibiting, or ameliorating the symptoms or conditions of a disease; inhibiting the development of complications; ameliorating or preventing underlying metabolic syndrome; inhibiting the development of a disease or symptom, such as controlling the progression of a disease or condition; alleviating a disease or symptom; causing a regression of a disease or symptom; alleviating complications caused by a disease or symptom, or preventing or treating signs caused by a disease or symptom. As used herein, a compound or pharmaceutical composition, upon administration, can improve a disease, symptom, or condition, particularly by improving its severity, delaying its onset, slowing its progression, or reducing its duration. Whether the administration is fixed or temporary, continuous or intermittent, the circumstances may be attributable to or related to the administration.

[0141] According to the present invention, "active ingredient" refers to the compound shown in formula (I), and the pharmaceutically acceptable inorganic or organic salt of the compound shown in formula (I). The compound of the present invention may contain one or more asymmetric centers (chiral centers or chiral axes), and therefore appear in the form of racemates, racemic mixtures, single enantiomers, diastereomeric compounds and single diastereomers. The asymmetric center that may exist depends on the properties of the various substituents on the molecule. Each such asymmetric center will independently produce two optical isomers, and all possible optical isomers and diastereomeric mixtures and pure or partially pure compounds are included within the scope of the present invention. The present invention is meant to include all such isomeric forms of these compounds.

[0142] According to the present invention, the terms "compound," "composition," "agent," or "medicine or medicament" are used interchangeably herein and refer to a compound or composition that, when administered to a subject (human or animal), is capable of inducing a desired pharmaceutical and / or physiological response through local and / or systemic effects.

[0143] According to the present invention, the term "administered," "administering," or "administration" refers to the direct administration of the compound or composition, or the administration of a prodrug, derivative, or analog of the active compound.

[0144] According to the present invention, a "safe and effective amount" refers to an amount of the compound sufficient to significantly improve the condition without causing serious side effects. The safe and effective amount of the compound is determined based on the specific circumstances of the subject, such as the age, condition, and duration of treatment.

[0145] According to the present invention, "pharmaceutically acceptable excipients or carriers" refer to: one or more compatible solid or liquid fillers or gel substances, which are suitable for human use and must have sufficient purity and sufficiently low toxicity. "Compatibility" here means that the components in the composition can be mixed with the compounds of the present invention and with each other without significantly reducing the efficacy of the compounds. Some examples of pharmacologically acceptable excipients or carriers include cellulose and its derivatives (such as sodium carboxymethyl cellulose, sodium ethyl cellulose, cellulose acetate, etc.), gelatin, talc, solid lubricants (such as stearic acid, magnesium stearate), calcium sulfate, vegetable oils (such as soybean oil, sesame oil, peanut oil, olive oil, etc.), polyols (such as propylene glycol, glycerol, mannitol, sorbitol, etc.), emulsifiers (such as ), wetting agents (such as sodium lauryl sulfate), colorants, flavorings, stabilizers, antioxidants, preservatives, pyrogen-free water, etc.

[0146] According to the present invention, the present invention provides methods for treating diseases using the compounds, antibody-drug conjugates, pharmaceutical compositions, or drug-device compositions of the present invention, including radiotherapy and chemotherapy combinations, wherein the diseases include but are not limited to cancer or benign tumors.

[0147] According to the present invention, in some embodiments, a method for treating cancer is provided, comprising administering to an individual in need thereof an effective amount of any of the aforementioned compounds, pharmaceutical compositions of antibody-drug conjugates. In other embodiments, the cancer is a blood cancer and a solid tumor, including but not limited to leukemia, breast cancer, lung cancer, pancreatic cancer, colon cancer, bladder cancer, brain cancer, urothelial cancer, prostate cancer, liver cancer, ovarian cancer, head and neck cancer, gastric cancer, mesothelioma, or all cancer metastases. According to the present invention, the tumor can be a central nervous system tumor, including a primary tumor and a tumor metastasized to the central nervous system, selected from at least one of colon cancer, gastric cancer, breast cancer, and lung cancer. Preferably, the tumor is selected from in situ lesions and / or metastatic lesions. Further preferably, the tumor is selected from central nervous system tumors and / or central nervous system metastatic lesions. The inventors have discovered that the camptothecin derivatives provided by the present invention have high tumor cell inhibitory activity when used to treat the above-mentioned diseases, and have great clinical value. As ADC toxins, they can further expand the safety window of ADC drugs. In addition, there is a large difference in activity before and after activation as prodrugs. Before activation, they will not cause harm to normal tissues, and only exert their activity after activation in tumor tissues. They have higher tumor cell inhibitory activity and better safety.

[0148] In a fourth aspect, the present invention provides an antibody-drug conjugate, in which the derivative described in the first aspect and / or the derivative prepared by the method described in the second aspect are connected to the antibody via a linker and / or directly coupled to the antibody. The antibody in the above-mentioned antibody-drug conjugate can be a monoclonal antibody, a bispecific antibody, or a nanobody, specifically HER2, HER3, CD25, CD30, c-MET, etc., or an antibody currently in public use; the linker can be a cleavable linker or a non-cleavable linker, the non-cleavable linker being a maleimide-type linker and / or a thiolhexanamide-type linker; the cleavable linker being a hydrazone bond, a carbonate, a polypeptide, a disulfide bond, or other linkers currently in public use. The camptothecin derivatives provided by the present invention contain different substituents in their structure with different activities. Derivatives that can be directly coupled to the antibody can be selected, or the linker can be fixed to the antibody through antibody modification technology, and then the camptothecin derivative can be coupled to the antibody.

[0149] Other terms in the present invention may be interpreted in a conventional manner in the art.

[0150] The present invention uses the following abbreviations: 1,2-dichloroethane (DCE); dichloromethane (DCM); methanol (MeOH); tetrahydrofuran (THF); dimethylformamide (DMF); triethylamine (TEA or Et3N); trifluoroacetic acid (TFA); di-tert-butyl dicarbonate ((Boc)2O); 2-(7-azobenzotriazole)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU); N,N-diisopropylethylamine (DIEA); palladium on carbon (Pd / C); acetic anhydride (Ac2O); nuclear magnetic resonance (NMR); liquid chromatography-mass spectrometry (LC-MS); thin layer chromatography (TLC); preparative liquid chromatography (pre-HPLC). The present invention will be described in detail below through examples.

[0151] In the following examples, unless otherwise specified, the reagents or raw materials used were conventional biochemical reagent-grade products, and Deruxtecan was purchased from Haoyuan Biopharmaceutical Technology Co., Ltd.

[0152] In the following examples, 1H-NMR (nuclear magnetic resonance hydrogen spectrum) was measured using a Varian Mercury 400 nuclear magnetic resonance instrument, and chemical shifts are expressed in δ (ppm); the silica gel used for separation was 200-300 mesh unless otherwise specified, and the ratios of the eluents were all by volume.

[0153] Unless otherwise specified, room temperature in the following examples refers to 25±5°C.

[0154] Example 1: Synthesis of Compound 1

[0155] The specific process includes:

[0156] (1) Synthesis of Compound 1B

[0157] 1 g of isotecan (Compound 1A, 1.88 mmol) was dissolved in 20 mL of DMF. 570 mg of triethylamine (Et3N, 5.64 mmol) and 1 g of di-tert-butyl dicarbonate ((Boc)2O, 4.59 mmol) were added under nitrogen protection. The mixture was stirred at room temperature under nitrogen protection. After 2 hours, the reaction was complete as determined by TLC. The mixture was poured into 500 mL of water and extracted three times with 500 mL of ethyl acetate (EA). The combined organic phases were washed twice with saturated brine, dried over anhydrous sodium sulfate (Na2SO4), filtered, concentrated, and purified on a silica gel column (eluent: MeOH:DCM (volume ratio 1:5)) to obtain Compound 1B (900 mg, 90% yield) as a yellow oil. LC-MS (ESI, M+H)+ =536.1.

[0158] (2) Synthesis of Compound 1C

[0159] At 0°C under nitrogen, 300 mg of compound 1B (0.56 mmol) was dissolved in a mixture of 0.15 mL of nitric acid and 9 mL of Ac2O. The mixture was stirred at 0°C under nitrogen for 1 hour, concentrated under reduced pressure, and purified on a silica gel column (eluent: MeOH:DCM (volume ratio 1:5)) to give compound 1C (160 mg, 49% yield) as a white solid (ESI, M+H). + =581.3.

[0160] (3) Synthesis of Compound 1

[0161] 160 mg of compound 1C (0.28 mmol) was dissolved in 5 mL of DCM. 1 mL of TFA was added at 0°C under nitrogen protection. The mixture was stirred at 0°C under nitrogen protection for 1 hour. The mixture was concentrated under reduced pressure and purified by preparative liquid chromatography (Pre-HPLC) to obtain a yellow solid compound 1 (30 mg, 23% yield). LC-MS (ESI, M+H) + =481.2. The corresponding hydrogen spectrum is shown in Figure 1.

[0162] 1 H-NMR(400MHz,DMSO-d6)δ8.47(s,3H),7.73(d,J=10.7Hz,1H),6.76(s,1H),5.72(s,1H ),5.49(s,3H),5.12(s,1H),3.09(s,2H),2.43(s,3H),2.26-1.99(m,4H),0.94(s,3H).

[0163] Example 2: Synthesis of Compound 2

[0164] The specific process includes:

[0165] At room temperature under nitrogen, 68 mg of compound 1 (0.14 mmol), 32 mg of 2-hydroxyacetic acid (0.42 mmol), and 80 mg of HATU (0.21 mmol) were sequentially dissolved in 20 mL of DMF. 54 mg of DIEA (0.42 mmol) was added, and the mixture was stirred at room temperature under nitrogen for 2 hours. After concentration under reduced pressure, the mixture was purified by Pre-HPLC to afford compound 2 (17 mg, 22% yield) as a yellow solid. LC-MS (ESI, M+H) +=539.3. The corresponding hydrogen spectrum is shown in Figure 2.

[0166] 1 H-NMR (400MHz, DMSO-d6) δ8.38(d,J=8.9Hz,1H),7.61(d,J=10.7Hz,1H),6.70(s,1H),5.58(s,1H),5. 45(s,3H),5.23(s,2H),3.94(s,2H),3.24–3.09(m,2H),2.40(s,3H),2.26–1.97(m,4H),0.92(s,3H).

[0167] Example 3: Synthesis of Compound 3

[0168] The specific process includes:

[0169] 14 mg of compound 2 (0.02 mmol) was dissolved in 3 mL of DMF. 6.99 mg of tetrahydroxydiboron (0.07 mmol) and 0.41 mg of 4,4'-bipyridine were added at 25°C under nitrogen, and the mixture was stirred for 4 minutes. The mixture was concentrated under reduced pressure and purified by Pre-HPLC to obtain compound 3 (6.7 mg, 45% yield) as a yellow solid. LC-MS (ESI, M+H) + =509.1. The corresponding hydrogen spectrum is shown in Figure 3.

[0170] 1 H-NMR (400MHz, DMSO-d6) δ8.35(d,J=8.9Hz,1H),7.61(d,J=11.0Hz,1H),6.98(s,1H),6.48(s,2H),5.49(s,2H),5.39(s,1H),5.3 1(s,1H),5.08(d,J=7.3Hz,2H),3.95(d,J=5.8Hz,2H),3.18–3.04(m,2H),2.33(s,3H),2.04(dd,J=7.4,2.1Hz,4H),0.89(s,3H).

[0171] Example 4: Synthesis of Compound 4

[0172] (1) Synthesis of Compound 1D

[0173] 800 mg of compound 1C was dissolved in 10 mL of DMF, followed by the addition of 372 mg of tetrahydroxydiboron (4.1 mmol) and 21.5 mg of 4,4'-bipyridine (0.13 mmol). The mixture was stirred at 25°C under nitrogen for 5 minutes. After the reaction was complete, 100 mL of water was added to terminate the reaction. Compound 1D (240 mg, 31% yield) was collected by filtration to obtain a yellow solid. LC-MS (ESI, M+H) + =551.2.

[0174] (2) Synthesis of compound 4

[0175] 240 mg of compound 1D (0.43 mmol) was dissolved in 5 mL of DCM. 1 mL of TFA was added at 25°C under nitrogen protection. The mixture was stirred at 25°C under nitrogen protection for 1 hour. The mixture was concentrated under reduced pressure and purified by preparative HPLC to obtain yellow compound 4 (40 mg, 20% yield). LC-MS (ESI, M+H) + =451.2. The corresponding hydrogen spectrum is shown in Figure 4.

[0176] 1 H-NMR (400MHz, DMSO-d6) δ8.41(s,3H),7.74(d,J=11.0Hz,1H),7.07(s,2H),6.55(s,1H),5.59(s,1H),5.44( s,1H),5.38(s,2H),5.02(s,1H),3.24(s,1H),3.06(t,J=13.8Hz,1H),2.38(s,3H),2.06(s,4H),0.92(s,3H).

[0177] Example 5: Synthesis of Compound 5

[0178] (1) Synthesis of Compound 1F

[0179] 150 mg of ixitecan (Compound 1A, 0.3 mmol) was dissolved in 40 mL of DMF. 3 mL of THF was added at 0°C under nitrogen to dissolve 107 mg of phenylchloroformate (0.6 mmol). 86 mg of Et3N (0.86 mmol) was then added, mixed, and stirred at room temperature for 2 hours. The reaction was terminated by adding 100 mL of water. Compound 1F (125 mg, 59% yield) was isolated by filtration as a yellow solid. LC-MS (ESI, M+H) + =556.0.

[0180] (2) Synthesis of compound 5

[0181] 40 mg of compound 1F (0.07 mmol) was dissolved in 1 mL of DCE. 22 mg of (1-methyl-2-nitro-1H-imidazol-5-yl)methanol (0.14 mmol) was added at 25°C under nitrogen protection. After stirring at 25°C for 5 minutes, the reaction temperature was raised to 85°C and stirring was continued under nitrogen protection for 16 hours. The mixture was then purified by preparative HPLC to obtain compound 5 (20.9 mg, 45% yield) as a white solid. LC-MS (ESI, M+H) + =619.0. The corresponding hydrogen spectrum is shown in Figure 5.

[0182] 1 H-NMR(400MHz,DMSO-d6)δ8.23(s,1H),7.75(s,1H),7.29(s,2H),6.51(s,1H),5.32(d,J=61.4Hz,7H),4.01(s,3H), 3.28-3.20(m,1H),3.16-3.04(m,1H),2.37(s,3H),2.29-2.18(m,1H),2.18-2.06(m,1H),1.86(s,2H),0.87(s,3H).

[0183] Test Example 1

[0184] Cell antiproliferative activity assay

[0185] Camptothecin derivatives 1-5 prepared in Examples 1-5 of the present invention, wherein compounds 1 and 4 have similar structures, and compounds 2 and 3 have similar structures, and compound 5 can be metabolized in tumor cells to produce deruxtecan (Compound 1A). The antiproliferative activity of camptothecin derivatives was determined by measuring the antiproliferative activity of compounds 1-5 and deruxtecan against gastric cancer (MKN45), colon cancer (HCT116), breast cancer (MCF7), and lung cancer (A549) cells.

[0186] The specific testing process is as follows:

[0187] The culture dishes containing MKN45, HCT116 cells and culture medium were placed in a 37°C, 5% CO2 incubator for culture. Cells in good growth condition were taken, the original culture medium was discarded, and the cells were resuspended and counted respectively with culture medium; the cell suspensions were added to 96-well plates, with 4000 cells per well, and incubated in a 37°C, 5% CO2 cell culture incubator for 24 hours; the drugs of compounds 1-5 were diluted and added to the drugs and cultured for 72 hours, and the ATP content of cancer cells in each well was measured by CellTiter-Lumi. ATP is the direct source of cell energy, so by detecting the ATP content in the cells, the proliferation and toxicity of the cells can be directly reflected. Prism software calculates the IC value based on the ATP content value. 50 The software uses the inhibition rate as the y value and the drug concentration as the x value to perform four-parameter curve fitting, and records the drug concentration value corresponding to the inhibition rate value between the maximum inhibition rate and the minimum inhibition rate (the software defaults to IC 50 value). IC 50 The calculation results are shown in Table 1:

[0188] Table 1

[0189] NA indicates that the data is under testing and / or validation.

[0190] The culture dishes containing MCF7, A549 cells and culture medium were placed in a 37°C, 5% CO2 incubator for culture. Cells in good growth condition were taken, the original culture medium was discarded, and the cells were resuspended in the culture medium and counted; the cell suspensions were added to 96-well plates, with 10,000 cells per well, and incubated in a 37°C, 5% CO2 cell culture incubator for 24 hours; the drugs of compounds 1-5 were diluted and added, and after 72 hours of culture, the reduction effect of the living cells in each well on the MTS tetrazolium compound was measured by adding the MTS substrate to generate a colored formazan dye soluble in the cell culture medium. The proliferation and toxicity status of the cells can be directly reflected by detecting the OD light absorption value at 490nm in the culture medium. The survival rate was obtained by calculating the ratio of the OD values ​​of the drug-treated group and the control non-drug-treated group and multiplying it by 100%. Prism software calculates the IC according to the survival rate of each sample. 50 The software uses the survival rate as the y value and the drug concentration as the x value to perform a four-parameter curve fitting, and records the drug concentration value corresponding to the survival rate value between the maximum survival rate and the minimum survival rate (the software defaults to IC 50 value). IC 50 The calculation results are shown in Table 2:

[0191] Table 2

[0192] NA indicates that the data is under testing and / or validation.

[0193] Compared to Deruxtecan, the nitro-containing compounds 1, 2, and 5 prepared by the present invention exhibit very weak in vitro antiproliferative activity against MKN45, HCT116, MCF7, and A549 cells. However, amino compound 3, which has a similar structure to compound 1, exhibits significantly superior antiproliferative activity against HCT116, MCF7, and A549 cells compared to Deruxtecan. Therefore, nitro compounds 1, 2, and 5 can be used as prodrugs, converting to active amino compounds under the catalysis of nitroreductase in hypoxic tumor cells, thereby killing cancer cells. Active amino compounds, due to the presence of convenient linking groups such as -OH or -NH2 in their side chains and their strong cellular activity, are suitable as small molecule toxins for ADCs.

[0194] Test Example 2

[0195] Evaluation of the efficacy of the compounds prepared in Example 2 and Example 3 in the Balb / c Nude mouse HCT116 subcutaneous tumor model

[0196] HCT116 (human colon cancer cells, Shanghai Runnuo Biotechnology Co., Ltd.) cells were cultured in 5A medium supplemented with 15 wt% fetal bovine serum, 100 units / ml penicillin, and 100 μg / ml streptomycin. The cells were continuously cultured in a cell culture incubator at 37°C with 5 vol% CO2, and passaged 2-3 times per week. When the cells reached the logarithmic growth phase, they were harvested, washed twice with serum-free medium, and resuspended in serum-free 5A medium for counting. The cells were harvested, counted, and inoculated into 36 6-8 week-old female Balb / c nude mice (purchased from Shanghai Jihui Laboratory Animal Husbandry Co., Ltd. and maintained in the animal room of Shanghai Runnuo Biotechnology Co., Ltd.).

[0197] Each Balb / c Nude mouse was subcutaneously inoculated with 0.1 mL of HCT116 tumor cell solution containing 50 wt% Matrigel (about 5.00 × 10 6 The day of inoculation was designated as day 0. When the mean tumor volume reached approximately 99 cubic millimeters, 24 mice were selected and randomly divided into groups of 8 mice per group based on tumor size and body weight using Excel. Dosing was performed on the day of grouping, and the dosage was calculated as follows:

[0198] The required dosage of compound 2 prepared in Example 2 is (average weight of mice = 30 g plus 30% loss): 25 mg; (2+6) mg / kg×0.03 kg / mouse×8 mice×10 times×130%=25 mg.

[0199] The required dosage of compound 3 prepared in Example 3 is (average weight of mice = 30 g plus 30% loss): 6 mg;

[0200] 2mg / kg×0.03kg / animal×8animals×10 times×130%=6mg.

[0201] The first group (G1) was a vehicle control group (5 wt% mannitol + 95 wt% citrate buffer, pH 6.5). The second group received compound 2 prepared in Example 2 (6 mg / kg in the first week, 12 mg / kg in the second week). The third group received compound 3 prepared in Example 3 (2 mg / kg in the first week, 1 mg / kg in the second week). Subcutaneous administration (volume 10 mg / kg body weight) was performed once daily for 5 consecutive days per week, followed by 2 days of rest, for a total of 2 weeks of administration and 4 weeks of observation.

[0202] The changes in mouse weight during the experiment are shown in Figure 6. As can be seen from Figure 6, the weight of mice inoculated with Compound 3 prepared in Example 3 decreased to a minimum around the 7th day of inoculation. Although there was some weight gain thereafter, the weight remained stable. The survival of the mice was significantly prolonged compared to the mice in the Compound 2 prepared in Example 2 and the vehicle control group. The changes in tumor volume during inoculation are shown in Figure 7. As can be seen from Figure 7, Compound 3 prepared in Example 3 can effectively inhibit the growth of tumor volume and prolong the survival period of mice.

[0203] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A camptothecin derivative, characterized in that, The derivative is a compound represented by formula (I) and / or a pharmaceutically acceptable salt thereof: Among them, R1 is selected from at least one of H, -NO2, -NH2, -OH and halogen; R2 is selected from at least one of H, acyl group and substituted acyl group, and R1 and R2 are not both H at the same time.

2. The derivative according to claim 1, wherein The halogen is selected from at least one of F, Cl and Br; Preferably, R1 is selected from at least one of H, -NO2 and -NH2, and R2 is hydrogen or substituted acyl group; Preferably, the substituted acyl group is at least one of hydroxy-substituted acyl group and / or alkoxy-substituted acyl group; Preferably, the hydroxy-substituted acyl group is α-hydroxy-substituted acyl group; further it is α-hydroxy-substituted acyl group containing C1-C6 alkane, more preferably α-hydroxyacetyl group; the alkoxy-substituted acyl group is alkoxy-substituted acyl group containing heterocycle and / or alkoxy-substituted acyl group containing nitro-substituted imidazole ring, further preferably alkoxy-substituted acyl group containing nitro-substituted imidazole ring, more preferably (1-methyl-2-nitro-1H-imidazol-5-yl)methoxycarbonyl group.

3. The derivative according to claim 1 or 2, characterized in that, The derivatives are selected from: at least one of; Preferably, the derivatives are selected from: at least one of the following.

4. A method for preparing camptothecin derivatives, characterized in that, The method comprises the following steps: Subject the compound shown in formula (II) and the reactant to a substitution reaction to obtain the compound shown in formula (III); Among them, the reactant is a reactant containing nitro and / or a reactant containing substituted acyl group; Ra is nitro and hydrogen; Rb is selected from at least one of acyl group, substituted acyl group and hydrogen, preferably substituted acyl group and hydrogen, and Ra and Rb are not both H at the same time; or (1) Subject the compound shown in formula (II) and the reactant to a substitution reaction to obtain the compound shown in formula (III); Among them, the reactant is a mixture of a reactant containing nitro and a reactant containing substituted acyl group or a reactant containing nitro; Ra is nitro, and Rb is substituted acyl group or hydrogen; (2) Subject the compound shown in formula (III) to a reduction reaction to obtain the compound shown in formula (IV); or (1) Subject the compound shown in formula (II) and the reactant to a substitution reaction to obtain the compound shown in formula (III); Among them, the reactant is a mixture of a reactant containing nitro and a reactant containing substituted acyl group or a reactant containing nitro; Ra is nitro, and Rb is substituted acyl group or hydrogen; (2) Subject the compound shown in formula (III) to a reduction reaction to obtain the compound shown in formula (IV); (3) Subject the compound shown in formula (IV) to a Sandmeyer reaction; or (1) Subject the compound shown in formula (II) and the reactant to a substitution reaction to obtain the compound shown in formula (III); Among them, the reactant is a mixture of a reactant containing nitro and a reactant containing substituted acyl group or a reactant containing nitro; Ra is nitro, and Rb is substituted acyl group or hydrogen; (2) Subject the compound shown in formula (III) to a reduction reaction to obtain the compound shown in formula (IV); (3) Perform Buchwald-Hartwig coupling reaction on the compound shown in formula (IV); 5. The method according to claim 4, characterized in that Before the substitution reaction, react the compound shown in formula (II) with an amino protecting agent; Preferably, the amino protecting agent is selected from at least one of benzyl chloroformate, di-tert-butyl dicarbonate and 9-fluorenylmethyl chloroformate.

6. The method according to claim 4, wherein The reactant containing nitro is nitric acid; The substituted acyl group is a hydroxy-substituted acyl group and / or an alkoxy-substituted acyl group; Preferably, the hydroxy-substituted acyl group is an α-hydroxy-substituted acyl group; further, it is an α-hydroxy-substituted acyl group containing a C1-C6 alkane, more preferably an α-hydroxyacetyl group; the alkoxy-substituted acyl group is an alkoxy-substituted acyl group containing a heterocycle and / or an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring, and more preferably an alkoxy-substituted acyl group containing a nitro-substituted imidazole ring; More preferably, the reactant containing a substituted acyl group is selected from glycolic acid, phenyl chloroformate, and methyl chloroformate (1-methyl-2-nitro-1H-imidazol-5-yl).

7. The method according to claim 4, characterized in that, In step (2), the reduction reaction includes contacting the compound shown in formula (III) with a reducing agent; Preferably, the reducing agent is tetrahydroxy diboron and / or sodium borohydride.

8. The method according to any one of claims 4-7, characterized in that When the reactant is a mixture of a reactant containing a nitro group and a reactant containing a substituted acyl group, the substitution reaction includes: The compound shown in formula (II) is subjected to a substitution reaction with a reactant containing a nitro group to obtain the compound shown in formula (V); then the compound shown in formula (V) is subjected to a substitution reaction with a reactant containing a substituted acyl group; Preferably, when the reactant is a reactant containing a nitro group, the conditions of the substitution reaction at least satisfy: protected by an inert gas, the temperature is -4 - 0°C, and the time is 50 - 70 min; When the reactant is a reactant containing a substituted acyl group, the conditions of the substitution reaction at least satisfy: protected by an inert gas, the temperature is 25 - 30°C, and the time is 120 - 130 min; The conditions of the reduction reaction at least satisfy: protected by an inert gas, the temperature is 20 - 25°C, and the time is 4 - 10 min.

9. Use of the derivative according to any one of claims 1 - 3 and the derivative prepared by the method according to any one of claims 4 - 8 in the preparation of an anti-tumor drug; Preferably, the anti-tumor drug is an antibody-drug conjugate; Preferably, the anti-tumor drug is a hypoxia-activated prodrug; Preferably, the anti-tumor drug is a small molecule active drug; Preferably, the tumor is selected from at least one of colon cancer, gastric cancer, breast cancer, and lung cancer; Preferably, the tumor is an in-situ lesion and / or a metastatic lesion; Preferably, the tumor is selected as a central tumor and / or a central metastatic lesion.

10. An antibody-drug conjugate, characterized in that, In the antibody-drug conjugate, the derivative according to any one of claims 1 - 3 and / or the derivative prepared by the method according to any one of claims 4 - 8 is connected to the antibody through a linker and / or directly conjugated to the antibody.

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