Polyboron complex, and preparation and use thereof

Abstract

Provided in the present invention are a polyboron complex or a stereoisomer, a deuterated compound or a pharmaceutically acceptable salt thereof, and the preparation and the use thereof. The polyboron complex of the present invention has a relatively low biotoxicity, and has a relatively high T / B ratio and boron enrichment level in tumor cells. The structure of the polyboron complex is as shown in the following formula (I).

Description

A polyboron complex and its preparation and application Technical Field

[0001] The present invention relates to the field of medicine, and in particular to a polyboron complex and its preparation and application. Background Art

[0002] Boron neutron capture therapy (BNCT) is a promising radiotherapy technique that selectively delivers 10 The B drug is introduced into cancer cells and then irradiated with low-energy neutrons, resulting in a highly localized nuclear fission reaction that releases energy and induces cell death. Because energy deposition is limited to the diameter of a single cell, tumor cells with significant boron accumulation will be damaged, leaving surrounding healthy cells unaffected. Boron compounds have been continually refined to create ideal BNCT compounds that can selectively target tumor cells and maintain a longer retention time within them.

[0003] First-generation boron compounds: In the early 1950s, compounds such as boric acid, borax, and pentaborate were synthesized. However, their concentrations in tumors were observed to be very low compared to those in the brain, and their accumulation was short-lived. Second-generation boron compounds: The 1960s saw the emergence of two of the most potent and prominent boron compounds: borylphenylalanine (BPA) and sodium boryldecanoate (BSH). They exhibited significantly lower toxicity in animal tumors and persisted longer in the tumor. Furthermore, the tumor / brain and tumor / blood boron concentration ratios were both greater than 1. Consequently, they have been authorized for clinical trials.

[0004] Compared to BSH, which has no tumor targeting ability, BPA is the most successful compound in current clinical trials, but its low solubility has always been a major problem in BNCT. 18 F)F-BPA is more soluble in lipids due to the presence of lipophilic fluorine. However, borate ester complexes between BPA and monosaccharides significantly improved its water solubility and soon entered the clinic for the treatment of patients with high-grade gliomas. In addition to the solubility problem, BPA also has other problems in BNCT: when exposed to sufficient concentrations of reactive oxygen species (ROS) generated in biological systems, such as hydrogen peroxide, peroxynitrite, oxygen free radicals, etc., boric acid undergoes metabolic instability. Compared with normal cells, cancer cells produce more ROS, which reduces 10 B accumulation in cancer cells.

[0005] The success of binary radiotherapy depends on the selective uptake of therapeutic doses of boron-containing agents by cancer cells, so the development of more effective and selective smart boron delivery agents is needed. Summary of the Invention

[0006] In view of the defects or deficiencies in the prior art, the present invention provides a polyboron complex, a single molecule containing two or more 10 B atoms can effectively improve cell 10 B uptake, can be applied to boron neutron capture therapy. After the introduction of tumor targeting fragments, the polyboron complex of the present invention can selectively accumulate in tumor cells, achieving the dual effects of tumor targeting and high uptake, and is expected to be further applied to boron neutron capture therapy.

[0007] Another object of the present invention is to provide a pharmaceutical composition.

[0008] Another object of the present invention is to provide a method for preparing the polyboron complex.

[0009] Another object of the present invention is to provide uses of the polyboron complex.

[0010] To achieve the above objectives, in one aspect, the present invention provides a polyboron complex or a stereoisomer, deuterated product or pharmaceutically acceptable salt thereof, wherein the polyboron complex structure is shown in the following formula (I):

[0011] R1 and R2 are each independently selected from: H, F, Cl, Br, I, -OH, -R'OH, alkyl, alkoxy, amino, nitro, cyano, alkylthio, alkenyl, alkynyl, cycloalkyl, cycloalkyloxy, cycloalkylthio, acyl, ester, amide, aryl, heterocyclyl, heteroaryl, heterocycloalkyl, monoalkylamino or dialkylamino;

[0012] R' is selected from substituted or unsubstituted alkylene groups having 1 to 6 carbon atoms; the substituted groups are selected from halogen, hydroxyl, amino, and nitro;

[0013] R3 is -OH,

[0014] R6 is selected from a single bond, an alkylene group having 1 to 3 carbon atoms;

[0015] R5 is selected from H, F, Cl, Br, I, hydroxyl or dihydroxyboryl;

[0016] a and b are each independently selected from 0, 1, 2, 3 or 4;

[0017] x is selected from 0, 1, 2, 3 or 4;

[0018] n is selected from 0, 1 or 2;

[0019] The above * is the connection site.

[0020] In order to achieve the purpose of solving the above-mentioned technical problems, the present invention adopts the principles of structural splicing and skeleton transition to design a polyboron complex, which is mainly obtained through multi-step reactions such as Schiff base and complexation, providing a new candidate intelligent boron delivery agent for boron neutron capture therapy.

[0021] According to some specific embodiments of the present invention,

[0022] R1 and R2 are each independently selected from: H, F, Cl, Br, I, -OH, -R'OH, alkyl, alkoxy, amino, nitro, cyano, alkylthio, alkenyl, alkynyl, cycloalkyl, cycloalkyloxy, cycloalkylthio, acyl, ester, amide, aryl, heterocyclyl, heteroaryl, heterocycloalkyl, monoalkylamino or dialkylamino;

[0023] R' is selected from substituted or unsubstituted alkylene groups having 1 to 6 carbon atoms; the substituted groups are selected from halogen, hydroxyl, amino, and nitro;

[0024] R3 is

[0025] R5 is selected from H, F, Cl, Br, I, hydroxyl or dihydroxyboryl;

[0026] a and b are each independently selected from 0, 1, 2, 3 or 4;

[0027] x is selected from 0, 1, 2, 3 or 4;

[0028] n is selected from 0, 1 or 2;

[0029] The above * is the connection site.

[0030] According to some specific embodiments of the present invention, the structure of the polyboron complex is shown in the following formula (II):

[0031] According to some specific embodiments of the present invention, the structure of the polyboron complex is as shown in the following formula (II-1) or (II-2):

[0032] According to some specific embodiments of the present invention, the structure of the polyboron complex is as shown in the following formula (II-1-1) or (II-2-1):

[0033] According to some specific embodiments of the present invention, for Preferably

[0034] According to some specific embodiments of the present invention, for

[0035] According to some specific embodiments of the present invention, Selected from R1 and R2 are each independently selected from H or methyl; preferably, R1 and R2 are each independently methyl. n is 1. a and b are each independently 0 or 1; preferably, a and b are each independently 1.

[0036] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from H, F, Cl, Br, I, -OH, -R'OH, nitro, cyano, C 1-10 Alkyl or C 1-10 Alkoxy.

[0037] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from F, Cl, Br, I, -OH, -R'OH, nitro, cyano, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, -CH(CH3)CH2CH2CH3, -CH2CH(CH3)CH2CH3, -CH2CH2CH(CH3)2, -CH(C2H5)CH2CH3, -C(CH3)2CH2CH3, -CH(CH3)CH(CH3)2, -CH2C(CH3)3, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy or tert-butoxy.

[0038] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from H, F, Cl, Br, I, -OH, -R'OH, nitro, cyano, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, -CH(CH3)CH2CH2CH3, -CH2CH(CH3)CH2CH3, -CH2CH2CH(CH3)2, -CH(C2H5)CH2CH3, -C(CH3)2CH2CH3, -CH(CH3)CH(CH3)2, -CH2C(CH3)3, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy or tert-butoxy.

[0039] According to some specific embodiments of the present invention, wherein said -R'OH is independently selected from: -CH2OH, -CH2CH2OH, -CH(OH)CH2OH, -CHFCH2OH, -CHClCH2OH, -CHFCHClOH, -CHBrCH2OH, -CHICH2OH, -CH(NH2)CH2OH, -CH(NO2)CH2OH, -CH(OH)CH2OH, -(CH2)3OH, -CHFCH2CH2OH, -CHFCH(OH)CH2OH, -CHClCH2CH2OH, -CH(OH)CH(OH)CH2OH, -CHFCHFCH2OH, -CH(CH2OH)CH2OH, -(CH2)4OH, -CH(OH)(CH2)3OH, -CHF(CH2)3OH, -CH(CH2OH )CH2CH2OH, -(CH2)5OH, -CH(OH)(CH2)4OH, -CHCl(CH2)4OH, -CHF(CH2)4OH, -CHBr(CH2)4OH, -CH(OH)CH(CH2OH)CH2CH2OH, -CH(OH)CH(OH)CH2CH2CH2OH, -CH(OH)CH(OH)CH2CH(OH)CH 2OH, -CH(CH2OH)CH(CH2OH)CH2OH, -(CH2)6OH, -CH(OH)CH(OH)CH2CH2CH2CH2OH, -CH(OH)(CH2)5OH, -CHF(CH2)5OH, -CH(OH)CH(CH2OH)CH2CH2CH2OH, -CH(CH2OH)CH(CH2OH)CH2CH2OH.

[0040] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from F, Cl, Br, I, -OH, -R'OH, methyl, methoxy or ethoxy.

[0041] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from H, F, Cl, Br, I, -OH, -R'OH, C 1-3 Alkyl or C 1-3 Alkoxy.

[0042] According to some specific embodiments of the present invention, R5 is selected from H, F, Cl, Br, I or hydroxyl, preferably H. x is selected from 0, 1, 2, 3 or 4, preferably 0 or 1.

[0043] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from H, F, Cl, Br, I, -OH, -R'OH, methyl, methoxy or ethoxy; R' is selected from a substituted or unsubstituted alkylene group having 1 to 3 carbon atoms; the substituted group is selected from a halogen, a hydroxyl group;

[0044] R5 is selected from H, F, Cl, Br, I, hydroxyl;

[0045] a and b are each independently selected from 0, 1 or 2;

[0046] x is selected from 0, 1, 2, 3 or 4;

[0047] n is selected from 0, 1 or 2.

[0048] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from F, Cl, Br, I, -OH, -R'OH, methoxy or ethoxy;

[0049] R5 is selected from H, F, Cl, Br or I;

[0050] a and b are each independently selected from 1 or 2;

[0051] x is 0, 1 or 2; preferably 0;

[0052] n is 1.

[0053] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from F, Cl, Br, I or -OH;

[0054] R5 is selected from H, F, Cl, Br or I;

[0055] a and b are each independently selected from 1 or 2;

[0056] x is 0 or 1; preferably 0;

[0057] n is 1.

[0058] According to some specific embodiments of the present invention, R1 and R2 are each independently selected from hydrogen, nitro, cyano, and methyl;

[0059] R5 is selected from H, F, Cl, Br or I; preferably H;

[0060] a and b are each independently selected from 1 or 2;

[0061] x is 0, 1 or 2; preferably 0;

[0062] n is 1.

[0063] According to some specific embodiments of the present invention, wherein, R1 and R2 are the same, a and b are the same, and R1 and R2 are bilaterally symmetrical with A-A' of the following formula (I) as the axis of symmetry:

[0064] It is understood that in formula (II), R1 and R2 may be the same, a and b may be the same, and R1 and R2 may be bilaterally symmetrical about AA' as the axis of symmetry similar to formula (I).

[0065] According to some specific embodiments of the present invention, the polyboron complex is selected from one of the following structures:

[0066] According to some specific embodiments of the present invention, the polyboron complex is selected from one of the following structures:

[0067] According to some specific embodiments of the present invention, the polyboron complex is selected from one of the following structures:

[0068] According to some specific embodiments of the present invention, the polyboron complex is selected from one of the following structures:

[0069] According to some specific embodiments of the present invention, at least one of the Bs in the polyboron complex is 10 B.

[0070] According to some specific embodiments of the present invention, wherein all B of the polyboron complex is 10 B.

[0071] In another aspect, the present invention further provides a method for preparing the polyboron complex or its stereoisomers, deuterated products or pharmaceutically acceptable salts, wherein the method comprises the steps of preparing the polyboron complex using compound (1) and compound (2) as raw materials:

[0072] R1 and R2 are each independently selected from the group consisting of H, F, Cl, Br, I, -OH, -R'OH, alkyl, alkoxy, amino, nitro, cyano, alkylthio, alkenyl, alkynyl, cycloalkyl, cycloalkyloxy, cycloalkylthio, acyl, ester, amide, aryl, heterocyclic, heteroaryl, heterocycloalkyl, monoalkylamino, or dialkylamino; R' is selected from the group consisting of substituted or unsubstituted alkylene groups having 1 to 6 carbon atoms; and the substituted groups are selected from the group consisting of halogen, hydroxyl, amino, and nitro.

[0073] R3 is R5 is selected from H, F, Cl, Br, I, hydroxyl or dihydroxyboryl; x is selected from 0, 1, 2, 3 or 4;

[0074] a and b are each independently selected from 0, 1, 2, 3 or 4;

[0075] n is selected from 0, 1 or 2;

[0076] The above * is the connection site.

[0077] In some embodiments, wherein for

[0078] In some embodiments, compound (2) is R5 and x are as shown above. Further, compound (2) can be That is, BPA (paraboronic phenylalanine); compound (2) can be That is, 3-BPA (boron phenylalanine); compound (2) can also be That is 2-BPA (o-boronophenylalanine).

[0079] In the examples of the present invention, compound (2) used in the preparation of the polyboron complex uses BPA (paraboron phenylalanine), and the polyboron complex number includes "BNC-4", which can be seen in the numbering of the example compounds for details; compound (2) used in the preparation of the polyboron complex uses 3-BPA (metaboron phenylalanine), and the polyboron complex number includes "BNC-3", which can be seen in the numbering of the example compounds for details.

[0080] In some embodiments, the method comprises: reacting compound (1) with compound (2) at 80-100°C.

[0081] In some embodiments, the method comprises reacting compound (1) with compound (2) at 80-100° C. for 18-30 hours.

[0082] The reaction solvent of compound (1) and compound (2) is at least one selected from acetonitrile, dichloroethane, N,N-dimethylformamide, and dimethyl sulfoxide. The molar ratio of compound (1) to compound (2) is 1:1.

[0083] According to some specific embodiments of the present invention, the method further comprises the step of preparing a compound of formula (1) using a compound of formula (3) and boric acid as raw materials:

[0084] Wherein R1, R2, a, b, and n are the same as those shown above.

[0085] Furthermore, in some embodiments, the method comprises: adding boric acid to the compound of formula (3) in an organic solvent, and reacting under the protection of an inert gas to obtain a polyboron complex at a reaction temperature of 80-100°C.

[0086] In some embodiments, the reaction time is 3 to 5 hours.

[0087] The organic solvent is selected from at least one of acetonitrile, dichloroethane, N,N-dimethylformamide, and dimethyl sulfoxide. The molar ratio of the compound of formula (3) to boric acid is 1:2.

[0088] According to some specific embodiments of the present invention, the method further comprises the step of preparing a compound of formula (3) using a compound of formula (4), a compound of formula (4') and a compound of formula (5) as raw materials:

[0089] Wherein R1, R2, a, b, and n are the same as those shown above.

[0090] Furthermore, in some embodiments, the method comprises: dissolving the compound of formula (4) and the compound of formula (4') in ethanol, adding ethylenediamine, reacting for 18 to 30 hours, adjusting the temperature of the reaction solution to 0 to 10°C after the reaction, and filtering to obtain the compound of formula (3).

[0091] In some embodiments, the molar ratio of the compound of formula (4 / 4') to the compound of formula (5) is 2: 1. That is, the molar ratio of the sum of the compound of formula (4) and the compound of formula (4') to the compound of formula (5) is 2:1.

[0092] According to some specific embodiments of the present invention, the compound of formula (4) and the compound of formula (4') have the same structure.

[0093] According to some specific embodiments of the present invention, the compound of formula (4) and the compound of formula (4') have different structures.

[0094] It can be imagined that when the structures of the compound of formula (4) and the compound of formula (4') are the same, the raw materials used are more simple and easier to obtain, and the products are also more simple. In addition, when the structures of the compound of formula (4) and the compound of formula (4') are different, the various products prepared therefrom are all polyboron complexes of the present invention.

[0095] According to some specific embodiments of the present invention, the compound of formula (4) and the compound of formula (4') are each independently selected from one of the following compounds:

[0096] On the other hand, the present invention also provides a pharmaceutical composition, wherein the pharmaceutical composition contains the polyboron complex according to any one of the present invention or its stereoisomer, deuterated product or pharmaceutically acceptable salt, and a pharmaceutically acceptable carrier.

[0097] According to some specific embodiments of the present invention, the pharmaceutical composition further comprises a cosolvent. Further, the cosolvent comprises galactose or fructose. The cosolvent can be prepared using a NaOH phosphate buffer.

[0098] According to some specific embodiments of the present invention, the pharmaceutical composition further contains galactose, and based on the total weight of the pharmaceutical composition as 100%, the weight percentage of the polyboron complex or its stereoisomers, deuterated substance or pharmaceutically acceptable salt is 0.05%-90%, and the weight percentage of the galactose is 40%-60%.

[0099] According to some specific embodiments of the present invention, the pharmaceutical composition further contains galactose, and based on the total weight of the pharmaceutical composition as 100%, the weight percentage of the polyboron complex or its stereoisomers, deuterated substance or pharmaceutically acceptable salt is 0.05%-90%, and the weight percentage of the galactose is 40% or 50% or 60%.

[0100] According to some specific embodiments of the present invention, the weight percentage of the polyboron complex or its stereoisomers, deuterated substances or pharmaceutically acceptable salts is 50%-90%.

[0101] According to some specific embodiments of the present invention, the method for preparing the pharmaceutical composition comprises: preparing the polyboron complex composition using a phosphate buffer solution containing NaOH.

[0102] In another aspect, the present invention further provides the use of the aforementioned polyboron complex or its stereoisomers, deuterated products or pharmaceutically acceptable salts, or the pharmaceutical composition of the present invention in the preparation of anti-tumor drugs.

[0103] According to some specific embodiments of the present invention, the tumor can be glioma, pancreatic cancer, triple-negative breast cancer, liver cancer, melanoma, head and neck tumor, brain tumor, meningioma, pleural mesothelioma, lung cancer, osteosarcoma, cervical cancer or bladder cancer.

[0104] According to some specific embodiments of the present invention, the tumor is a central nervous system tumor or breast cancer.

[0105] In some embodiments, the tumor may also be other cancer types for which BNCT drugs (such as BPA) are applicable.

[0106] According to some specific embodiments of the present invention, the anti-tumor drug is an anti-tumor drug used under neutron irradiation conditions.

[0107] According to some specific embodiments of the present invention, the anti-tumor drug is a drug used for boron neutron capture therapy.

[0108] In summary, the present invention provides a polyboron complex and its preparation and application.

[0109] The polyboron complex of the present invention has the following advantages:

[0110] The present invention provides novel polyboron complexes. These compounds are prepared from readily available raw materials using inexpensive, readily available reagents, and are simple to operate and easy to prepare. The present synthesis method exhibits mild reaction conditions, high yields, and is economical and practical. The present compounds and their synthesis methods are reported for the first time.

[0111] The polyboron complex of the present invention has low biological toxicity and has a high T / B ratio and boron enrichment in tumor cells.

[0112] The present invention can be used as a boron drug for BNCT and has excellent application prospects in the field of anti-tumor. BRIEF DESCRIPTION OF THE DRAWINGS

[0113] Figures 1 to 9 show the cytotoxicity test results of Experimental Example 1.

[0114] 10 to 13 are graphs showing the boron uptake capacity evaluation data of Experimental Example 2. FIG.

[0115] 14 to 16 are graphs showing in vitro activity evaluation data of Application Example 1.

[0116] FIG17 shows the UV measurement results of Experimental Example 3.

[0117] 18 and 19 show the fluorescence measurement results of Experimental Example 4.

[0118] 20 to 23 show the cell safety measurement results of Experimental Example 5.

[0119] FIG24 and FIG25 are the results of the cell uptake experiment of Experimental Example 6.

[0120] Figures 26 and 27 show the BNCT efficacy results of Application Example 2.

[0121] FIG28 and FIG29 are the results of the in vivo boron distribution study of Application Example 3. DETAILED DESCRIPTION

[0122] The following describes in detail the implementation process of the present invention and the beneficial effects produced by specific embodiments, which is intended to help readers better understand the essence and characteristics of the present invention and is not intended to limit the scope of implementation of this case.

[0123] Unless otherwise defined, all technical terms herein have the same meaning as commonly understood by those skilled in the art to which the subject matter of the claims belongs. It should be understood that the above brief description and the detailed description below are exemplary and are only used for explanation, and do not impose any restrictions on the subject matter of the present invention. In this application, unless otherwise specifically stated, the use of the singular also includes the plural. It should be noted that, unless otherwise clearly stated in the text, the singular forms used in this specification and claims include the plural forms of the things referred to. It should also be noted that, unless otherwise stated, the use of "or" and "or" means "and / or". In addition, the use of the term "including" and other forms, such as "comprising", "containing" and "containing" are not restrictive.

[0124] In addition to the foregoing, when used in the specification and claims of this application, the following terms have the meanings indicated below unless otherwise specifically stated.

[0125] The term "alkenyl" refers to an unbranched or branched monovalent hydrocarbon chain containing one or more carbon-carbon double bonds, including but not limited to C2-3 alkenyl, C2-4 alkenyl, or C2-5 alkenyl.

[0126] The term "alkynyl" refers to an unbranched or branched monovalent hydrocarbon chain containing one or more carbon-carbon triple bonds, including but not limited to C2-3 alkynyl, C2-4 alkynyl, or C2-5 alkynyl.

[0127] The term "cycloalkyl" or "carbocyclyl" refers to an alkyl group that is cyclic and contains 3 to 15, 3 to 9, 3 to 6, or 3 to 5 carbon atoms, with alternating or resonant double bonds between the carbon atoms. It may contain 1 to 4 rings. Examples of unsubstituted cycloalkyls include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and adamantyl. The cycloalkyl group may be substituted with one or more substituents. In some embodiments, the cycloalkyl group may be a cycloalkyl group fused to an aryl or heteroaryl group.

[0128] The term "heterocycloalkyl" or "heterocyclic radical" refers to a cycloalkyl group in which one or more, in some embodiments, 1 to 3 carbon atoms are replaced by heteroatoms, such as, but not limited to, N, O, and S. In some embodiments, heterocycloalkyl contains 3 to 15, 3 to 9, 3 to 6, or 3 to 5 carbons and heteroatoms. In some embodiments, heterocycloalkyl can be a heterocycloalkyl group fused to an aryl or heteroaryl group. When a prefix such as C3-6 is used to represent heterocycloalkyl, the number of carbon atoms (3-6 in this example) is also meant to include heteroatoms. For example, C3-6 heterocycloalkyl is meant to include, for example, tetrahydropyranyl (five carbon atoms and one heteroatom replacing the carbon atom).

[0129] The term "aryl" refers to a carbocyclic aromatic ring containing 5 to 14 ring atoms. The ring atoms of a carbocyclic aryl are all carbon atoms. Aryl ring structures include compounds with one or more ring structures, such as monocyclic, bicyclic, or tricyclic compounds, as well as benzo-fused carbocyclic moieties, such as 5,6,7,8-tetrahydronaphthyl. Specifically, an aryl group can be monocyclic, bicyclic, or tricyclic. Representative aryl groups include phenyl, anthracenyl, fluorenyl, indenyl, phenanthrenyl, and naphthyl.

[0130] The term "heteroaryl" refers to a monocyclic or polycyclic aromatic ring system. In certain embodiments, one to three atoms in the ring system are heteroatoms, i.e., elements other than carbon, including but not limited to N, O, or S. The heteroaryl group may be optionally fused to a benzene ring. Heteroaryl groups include, but are not limited to, furanyl, imidazolyl, indolinyl, pyrrolidinyl, pyrimidinyl, tetrazolyl, thienyl, pyridyl, pyrrolyl, N-methylpyrrolyl, quinolinyl, and isoquinolinyl.

[0131] The term "stereoisomer" refers to isomers resulting from different arrangements of atoms in a molecule in space, including but not limited to cis-trans isomers, enantiomers, and diastereomers.

[0132] The present invention is further described below with reference to specific embodiments.

[0133] Example 1

[0134] This embodiment provides a polyboron complex (Compound A), the structure of which is shown below:

[0135] The preparation method of compound A comprises the following steps:

[0136] (1) Compound 2,4-dihydroxybenzaldehyde (1a, 1.38 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC until completion. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.52 g of a yellow solid, thereby obtaining compound 2a with a yield of 96.8%.

[0137] (2) Compound 2a (314 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 61mg of boric acid ( 10 B, 1 mmol), heated under reflux at 80-100°C for 18-30 h, and the reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 323 mg of the product with a yield of 78.8%.

[0138] The product spectrum data is: ESI-MS (m / z): 408 [M+H] + ;

[0139] 1 H NMR (300MHz, DMSO-d6) δ8.36(s,2H),7.27(d,J=8.6Hz,2H),6.32(dd,J=8.5,2.2Hz,2H),6.19(d, J=2.1Hz,2H),3.84–3.57(m,4H),2.89(s,1H),2.73(s,1H),2.44–2.30(m,1H),1.96–1.90(m,1H).

[0140] Example 2

[0141] This embodiment provides a polyboron complex, the structure of which is shown below:

[0142] Referring to the synthesis method in Example 1, p-hydroxyphenylboronic acid ( 10 B) replaced the boric acid in the method to obtain a light yellow solid product with a yield of 80.4%.

[0143] The product spectrum data is: ESI-MS (m / z): 484 [M+H] + ;

[0144] 1H NMR (500MHz, DMSO-d6) δ8.49–8.32(m,2H),7.45–7.12(m,4H),6.52–6.05(m,6H),3.84–3.54(m,4H),2.09(s,2H).

[0145] Example 3

[0146] This embodiment provides a polyboron complex, the structure of which is shown below:

[0147] Referring to the synthesis method in Example 1, 4-hydroxymethylphenylboronic acid ( 10 B) replaced the boric acid in the method to obtain a light yellow solid product with a yield of 82.1%.

[0148] The product spectrum data is: ESI-MS (m / z): 498 [M+H] + ;

[0149] 1 H NMR (500MHz, DMSO-d6) δ8.52–8.34(m,2H),7.49–7.10(m,4H),6.50–6.08(m,6H),3.90–3.48(m,6H),2.03–1.92(m,2H).

[0150] Example 4

[0151] This embodiment provides a polyboron complex (4OH-BNC-4), the structure of which is shown below:

[0152] The preparation method of the polyboron complex (4OH-BNC-4) of this embodiment comprises the following steps:

[0153] (1) Compound 2,4-dihydroxybenzaldehyde (1a, 1.38 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC until completion. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.52 g of a yellow solid, thereby obtaining compound 2a with a yield of 96.8%.

[0154] (2) Compound 2a (314 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 4-boronic acid-L-phenylalanine ( 10B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h, and the reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 4OH-BNC-4462 mg with a yield of 82.9%.

[0155] Spectral data of 4OH-BNC-4: ESI-MS (m / z): 555 [M+H] + ; 1 H NMR(300MHz,DMSO-d6)δ8.36(s,2H),7.27(d,J=8.6Hz,4H),6.43–6.09(m,6H),3.69(dt,J=20 .7,10.1Hz,6H),2.89(s,2H),2.73(d,J=0.6Hz,2H),2.35(d,J=8.1Hz,1H),2.14–1.85(m,2H).

[0156] Example 5

[0157] This embodiment provides a polyboron complex, the structure of which is shown below:

[0158] The preparation method of the compound of this embodiment comprises the following steps:

[0159] Referring to the synthesis method in Example 1, 2,5-dihydroxybenzaldehyde (1b) was used instead of (1a) to obtain a yellow solid (2b) with a yield of 97.1%.

[0160] Referring to the synthesis method in Example 1, (2b) is substituted for (2a) in the method, and 4-boronic acid-L-phenylalanine ( 10 B) replaced the boric acid in the method to obtain a light yellow solid product with a yield of 79.7%.

[0161] The product spectrum data is: ESI-MS (m / z): 555 [M+H] + ;

[0162] 1 H NMR (300MHz, DMSO-d6) δ8.38(s,2H),7.28(s,4H),6.45–6.11(m,6H),3.72–3.42(m,6H),2.90(s,2H),2.74(s,2H),2.36(s,1H),2.12–1.88(m,2H).

[0163] Example 6

[0164] This embodiment provides a polyboron complex, the structure of which is shown below:

[0165] The preparation method of the polyboron complex of this embodiment comprises the following steps:

[0166] Referring to the synthesis method in Example 1, 2,4,5-trihydroxybenzaldehyde (1c) was used instead of (1a) to obtain a yellow solid (2c) with a yield of 96.5%.

[0167] Referring to the synthesis method in Example 1, (2c) is used instead of (2a) in the method, and 4-boronic acid-L-phenylalanine ( 10 B) replaced the boric acid in the method to obtain a light yellow solid product with a yield of 76.1%.

[0168] The product spectrum data is: ESI-MS (m / z): 587 [M+H] + ;

[0169] 1 H NMR(500MHz,DMSO-d6)δ8.38(s,1H),7.29(s,4H),6.45–6.11(m,5H),3.71–3.41(m,6H),2.91(s,2H),2.72(s,2H),2.35(s,1H),2.11–1.86(m,2H).

[0170] Example 7

[0171] This embodiment provides a polyboron complex, the structure of which is shown below:

[0172] The preparation method of the polyboron complex comprises the following steps:

[0173] Referring to the synthesis method in Example 1, 2-hydroxy-5-hydroxymethylbenzaldehyde (1d) was used instead of (1a) to obtain a yellow solid (2d) with a yield of 92.5%.

[0174] Referring to the synthesis method in Example 1, (2d) is used instead of (2a) in the method, and 4-boronic acid-L-phenylalanine ( 10 B) replaced the boric acid in the method to obtain a light yellow solid product with a yield of 72.0%.

[0175] The product spectrum data is: ESI-MS (m / z): 583 [M+H] + ;

[0176] 1H NMR(300MHz,DMSO-d6)δ8.36(s,2H),7.26(s,4H),6.46–6.10(m,6H),3.85 –3.34(m,10H),2.91(s,2H),2.73(s,2H),2.35(s,1H),2.10–1.85(m,2H).

[0177] Example 8

[0178] This embodiment provides a polyboron complex (4F-BNC-4), the structure of which is shown below:

[0179] The preparation method of the polyboron complex (4F-BNC-4) of this embodiment comprises the following steps:

[0180] Referring to the synthesis method in Example 1, 2-hydroxy-4-fluorobenzaldehyde (1e) was used instead of (1a) to obtain a yellow solid (2e) with a yield of 95.9%.

[0181] Referring to the synthesis method in Example 1, (2e) is used instead of (2a) in the method, and 4-boronic acid-L-phenylalanine ( 10 B) replaced the boronic acid in the method to obtain a pale yellow solid (4F-BNC-4) with a yield of 83.4%.

[0182] Spectral data of 4F-BNC-4: ESI-MS (m / z): 559 [M+H] + ;

[0183] 1 H NMR (300MHz, DMSO-d6) δ8.37(s,2H),7.26(s,4H),6.46–6.14(m,6H),3.74–3.46(m,6H),2.92(s,2H),2.76(s,2H),2.36(s,1H),2.11–1.89(m,2H).

[0184] Example 9

[0185] This embodiment provides a polyboron complex (4Br-BNC-4), the structure of which is shown below:

[0186] The preparation method of the polyboron complex (4Br-BNC-4) of this embodiment comprises the following steps:

[0187] Referring to the synthesis method in Example 1, 2-hydroxy-4-bromobenzaldehyde (1f) was used instead of (1a) to obtain a yellow solid (2f) with a yield of 98.0%.

[0188] Referring to the synthesis method in Example 1, (2f) was used instead of (2a) in the method, and 4-boronic acid-L-phenylalanine ( 10 B) replaced the boronic acid in the method to obtain a pale yellow solid (4Br-BNC-4) with a yield of 76.7%.

[0189] Spectral data of 4Br-BNC-4: ESI-MS (m / z): 679 [M+H] + ;

[0190] 1 H NMR (300MHz, DMSO-d6) δ8.37(s,2H),7.27(s,4H),6.42–6.08(m,6H),3.70–3.42(m,6H),2.88(s,2H),2.72(s,2H),2.35(s,1H),2.11–1.87(m,2H).

[0191] Example 10

[0192] This embodiment provides a polyboron complex (4OH-BNC-3), which is synthesized according to the steps of the above embodiment, and has the following structure:

[0193] Referring to the synthesis method in Example 4, a yellow solid (2a) was obtained with a yield of 98.0%.

[0194] Referring to the synthesis method in Example 4, 3-boronic acid-L-phenylalanine ( 10 B) replaced the boronic acid in the method to obtain 445 mg of a light yellow solid (4OH-BNC-3) with a yield of 79%.

[0195] Spectral data of 4OH-BNC-3: ESI-MS (m / z): 555 [M+H] + ;

[0196] 1 H NMR (300MHz, DMSO-d6) δ8.37(s,2H),7.27(s,4H),6.42–6.08(m,6H),3.70–3.42(m,6H),2.92(s,2H),2.93(s,2H),2.35(s,1H),2.11–1.87(m,2H).

[0197] Example 11

[0198] This embodiment provides a polyboron complex (4F-BNC-3), which is synthesized according to the steps of the above embodiment, and has the following structure:

[0199] Referring to the synthesis method in Example 4, 2-hydroxy-4-fluorobenzaldehyde (1e) was used instead of (1a) to obtain a yellow solid (2e) with a yield of 95.9%.

[0200] Referring to the synthesis method in Example 4, (2e) is substituted for (2a) in the method, and 3-boronic acid-L-phenylalanine ( 10 B) replaced the boronic acid in the method to obtain a light yellow solid (4F-BNC-3) with a yield of 80.4%.

[0201] Spectral data of 4F-BNC-3: ESI-MS (m / z): 559 [M+H] + ;

[0202] 1 H NMR (300MHz, DMSO-d6) δ8.37(s,2H),8.26(s,4H),7.46–6.14(m,6H),3.74–3.41(m,6H),2.92(s,2H),2.76(s,2H),2.36(s,1H),2.11–1.89(m,2H).

[0203] Example 12

[0204] This embodiment provides a polyboron complex (4H-BNC-4), which is synthesized according to the steps of the above embodiment, and has the following structure:

[0205] Referring to the synthesis method in Example 4, 2-hydroxybenzaldehyde (1 g) was used instead of step (1a) to obtain a yellow solid (2 g) with a yield of 98.0%.

[0206] Referring to the synthesis method in Example 4, (2g) was used instead of (2a) in the method, and 4-boronic acid-L-phenylalanine ( 10 B) replaced the boronic acid in the method to obtain a light yellow solid (4H-BNC-4) with a yield of 78.7%.

[0207] 4H-BNC-4 spectrum data: ESI-MS (m / z): 524 [M+H] + ;

[0208] 1H NMR (300MHz, DMSO-d6) δ8.37(s,2H),7.27(s,4H),6.42–6.08(m,6H),3.87–3.42(m,6H),2.95(s,2H),2.72(s,2H),2.35(s,1H),2.11–1.87(m,2H).

[0209] Example 13

[0210] This embodiment provides a polyboron complex (4H-BNC-3), which is synthesized according to the steps of the above embodiment, and has the following structure:

[0211] Referring to the synthesis method in Example 4, 2-hydroxybenzaldehyde (1 g) was used instead of step (1a) to obtain a yellow solid (2 g) with a yield of 98.0%.

[0212] Referring to the synthesis method in Example 4, (2g) was used instead of (2a) in the method, and 3-boronic acid-L-phenylalanine ( 10 B) replaced the boronic acid in the method to obtain a pale yellow solid (4H-BNC-3) with a yield of 75.6%.

[0213] 4H-BNC-3 spectrum data: ESI-MS (m / z): 524 [M+H] + ;

[0214] 1 H NMR (300MHz, DMSO-d6) δ8.37(s,2H),7.27(s,4H),6.42–6.08(m,6H),3.97–3.42(m,6H),2.75(s,2H),2.62(s,2H),2.35(s,1H),2.11–1.87(m,2H).

[0215] Example 14

[0216] This embodiment provides a polyboron complex, the structure of which is as follows:

[0217] With reference to the steps of the above-mentioned embodiment, the synthetic route is as follows:

[0218] Referring to the synthesis method in Example 4, 1,2-ethylenediamine was used instead of 1,2-propylenediamine to obtain a yellow solid (2h) with a yield of 95.0%.

[0219] Referring to the synthesis method in Example 4, (2h) was used to replace (2a) in the method, and 4-boronic acid-L-phenylalanine ( 10B) replaced the boric acid in the method to obtain a light yellow solid product with a yield of 78.6%.

[0220] The product spectrum data is: ESI-MS (m / z): 542 [M+H] + ;

[0221] 1 H NMR (300MHz, DMSO-d6) δ9.37(s,2H),7.87(s,4H),6.82–6.08(m,6H),4.97–3.42(m,6H),3.75(s,2H),2.62(s,2H),2.35(s,1H),2.11–1.87(m,2H).

[0222] Example 15

[0223] This embodiment provides a polyboron complex, which is synthesized according to the steps of the above embodiment, and has the following structure:

[0224] Referring to the synthesis method in Example 4, 1,2-ethylenediamine was used instead of 1,2-propylenediamine to obtain a yellow solid (2h) with a yield of 95.0%.

[0225] Referring to the synthesis method in Example 4, (2h) was used to replace (2a) in the method, and 3-boronic acid-L-phenylalanine ( 10 B) replaces the boric acid in the method to obtain a light yellow solid product with a yield of 79.6%.

[0226] The product spectrum data is: ESI-MS (m / z): 542 [M+H] + ;

[0227] 1 H NMR (300MHz, DMSO-d6) δ9.37(s,2H),7.87(s,4H),6.72–6.08(m,6H),4.97–3.32(m,6H),3.65(s,2H),2.62(s,2H),2.35(s,1H),2.11–1.87(m,2H).

[0228] Example 16

[0229] This embodiment provides a polyboron complex, the structure of which is as follows:

[0230] With reference to the steps of the above-mentioned embodiment, the synthetic route is as follows:

[0231] Referring to the synthesis method in Example 4, 1,4-butanediamine was used instead of 1,2-propylenediamine to obtain a yellow solid (2i) with a yield of 92.0%.

[0232] Referring to the synthesis method in Example 4, (2i) is substituted for (2a) in the method, and 4-boronic acid-L-phenylalanine ( 10 B) replaced the boric acid in the method to obtain a light yellow solid product with a yield of 73.6%.

[0233] The product spectrum data is: ESI-MS (m / z): 570 [M+H] + ;

[0234] 1 H NMR (300MHz, DMSO-d6) δ9.37(s,2H),8.87(s,4H),7.82–5.08(m,6H),4.97–4.42(m,6H),3.75(s,2H),2.62(s,2H),2.35(s,1H),2.11–1.87(m,2H).

[0235] Example 17

[0236] This embodiment provides a polyboron complex, which is synthesized according to the steps of the above embodiment, and has the following structure:

[0237] Referring to the synthesis method in Example 4, 1,4-butanediamine was used instead of 1,2-propylenediamine to obtain a yellow solid (2i) with a yield of 92.0%.

[0238] Referring to the synthesis method in Example 4, (2i) was used to replace (2a) in the method, and 3-boronic acid-L-phenylalanine ( 10 B) replaced the boric acid in the method to obtain a light yellow solid product with a yield of 68.6%.

[0239] The product spectrum data is: ESI-MS (m / z): 570 [M+H] + ;

[0240] 1 H NMR (300MHz, DMSO-d6) δ9.37(s,2H),7.87(s,4H),6.82–5.08(m,6H),4.97–342(m,6H),2.75(s,2H),2.62(s,2H),2.35(s,1H),2.11–1.87(m,2H).

[0241] Example 18

[0242] This embodiment provides a polyboron complex (4-Me-BNC-4 or 4CH3-BNC-4), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0243] (1) Compound 2,4-dihydroxybenzaldehyde (1j, 1.36 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC until completion. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.51 g of a yellow solid, thereby obtaining compound 2j with a yield of 97.4%.

[0244] (2) Compound 2j (316 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 4-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h. The reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 473 mg of 4-Me-BNC-4 (4CH3-BNC-4) with a yield of 85.5%.

[0245] Spectral data of 4-Me-BNC-4: ESI-MS (m / z): 553 [M+H] + ;

[0246] 1 H NMR(300MHz,DMSO-d6)δ8.36(s,2H),7.22(d,J=8.6Hz,4H),6.43–6.19(m,6H),3.59(dt,J=20 .7,10.1Hz,6H),2.84(s,2H),2.73(d,J=0.6Hz,2H),2.32(d,J=8.1Hz,1H),2.14–1.85(m,2H).

[0247] Example 19

[0248] This embodiment provides a polyboron complex (4-Me-BNC-3 or 4CH3-BNC-3), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0249] (1) Compound 2,4-dihydroxybenzaldehyde (1j, 1.36 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC until completion. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.51 g of a yellow solid, thereby obtaining compound 2j with a yield of 97.4%.

[0250] (2) Compound 2j (316 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 3-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h. The reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 475 mg of 4-Me-BNC-3 (4CH3-BNC-3) in a yield of 85.9%.

[0251] Spectral data of 4-Me-BNC-3: ESI-MS (m / z): 553 [M+H] + ;

[0252] 1 H NMR(300MHz,DMSO-d6)δ8.36(s,2H),7.21(d,J=8.6Hz,4H),6.43–6.18(m,6H),3.56(dt,J=20 .7,10.1Hz,6H),2.82(s,2H),2.73(d,J=0.6Hz,2H),2.3(d,J=8.1Hz,1H),2.14–1.85(m,2H).

[0253] Example 20

[0254] This embodiment provides a polyboron complex (4Cl-BNC-4), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0255] (1) Compound 4-chloro-2-hydroxybenzaldehyde (1k, 1.56 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.51 g of a yellow solid, resulting in compound 2k with a yield of 86%.

[0256] (2) Compound 2k (351 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 4-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h, and the reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 4-Cl-BNC-4474 mg with a yield of 79.8%.

[0257] Spectral data of 4-Cl-BNC-4: ESI-MS (m / z): 593 [M+H] + ;

[0258] 1 H NMR (300MHz, DMSO-d6) δ8.34(s,2H),7.2(d,J=8.6Hz,4H),6.42–6.19(m,6H),3.59(dt,J=20. 7,10.1Hz,6H),2.84(s,2H),2.73(d,J=0.6Hz,2H),2.31(d,J=8.1Hz,1H),2.14–1.85(m,2H).

[0259] Example 21

[0260] This embodiment provides a polyboron complex (4Cl-BNC-3), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0261] (1) Compound 4-chloro-2-hydroxybenzaldehyde (1k, 1.56 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.51 g of a yellow solid, resulting in compound 2k with a yield of 86%.

[0262] (2) Compound 2k (351 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 3-boronic acid-L-phenylalanine ( 10B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h, and the reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 473 mg of 4-Cl-BNC-3 in a yield of 79.8%.

[0263] Spectral data of 4-Cl-BNC-3: ESI-MS (m / z): 593 [M+H] + ;

[0264] 1 H NMR(300MHz,DMSO-d6)δ8.36(s,2H),7.21(d,J=8.6Hz,4H),6.41–6.16(m,6H),3.53(dt,J=20 .7,10.1Hz,6H),2.82(s,2H),2.71(d,J=0.6Hz,2H),2.2(d,J=8.1Hz,1H),2.14–1.85(m,2H).

[0265] Example 22

[0266] This embodiment provides a polyboron complex (4Br-BNC-3), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0267] (1) Compound 4-bromo-2-hydroxybenzaldehyde (1l, 2.01 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC to determine completion. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.98 g of a yellow solid, yielding compound 2l in 90% yield.

[0268] (2) Compound 21 (440 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 3-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h, and the reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 473 mg of 4-Br-BNC-3 in a yield of 69.3%.

[0269] Spectral data of 4-Br-BNC-3: ESI-MS (m / z): 553 [M+H] +;1H NMR(300MHz,DMSO-d6)δ8.36(s,2H),7.21(d,J=8.5Hz,4H),6.41–6.16(m,6H),3.51(dt,J=2 0.7,10.1Hz,6H),2.8(s,2H),2.7(d,J=0.6Hz,2H),2.1(d,J=8.1Hz,1H),2.13–1.88(m,2H).

[0270] Example 23

[0271] This embodiment provides a polyboron complex (4NO2-BNC-4), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0272] (1) Dissolve 2-hydroxy-4-nitrobenzaldehyde (1 m, 1.67 g, 10 mmol) in 80-200 mL of ethanol, add propylenediamine (0.37 g, 5 mmol), and reflux for 18-30 h. The reaction is complete after monitoring by TLC. The reaction solution is cooled to 0-10°C and filtered with a vacuum pump to obtain 1.6 g of a yellow solid, thereby obtaining compound 2m with a yield of 86%.

[0273] (2) Compound 2m (372 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 4-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h. The reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 4-NO2-BNC-4500 mg in a yield of 81.4%.

[0274] Spectral data of 4-NO2-BNC-4: ESI-MS (m / z): 614 [M+H] + ;

[0275] 1 H NMR(300MHz,DMSO-d6)δ8.34(s,2H),7.21(d,J=8.6Hz,4H),6.42–6.18(m,6H),3.58(dt,J=20 .6,10.2Hz,6H),2.82(s,2H),2.73(d,J=0.6Hz,2H),2.31(d,J=8.1Hz,1H),2.14–1.85(m,2H).

[0276] Example 24

[0277] This embodiment provides a polyboron complex (4NO2-BNC-3), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0278] (1) Dissolve 2-hydroxy-4-cyanobenzaldehyde (1 m, 1.67 g, 10 mmol) in 80-200 mL of ethanol, add propylenediamine (0.37 g, 5 mmol), and reflux for 18-30 h. The reaction is complete after monitoring by TLC. The reaction solution is cooled to 0-10°C and filtered with a vacuum pump to obtain 1.71 g of a yellow solid, thereby obtaining compound 2m with a yield of 91.9%.

[0279] (2) Compound 2m (372 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 3-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h. The reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 4-NO2-BNC-3498 mg with a yield of 81.1%.

[0280] Spectral data of 4-NO2-BNC-3: ESI-MS (m / z): 614 [M+H] + ;

[0281] 1 H NMR (300MHz, DMSO-d6) δ8.36 (s, 2H), 7.2 (d, J = 8.6Hz, 4H), 6.4–6.15 (m, 6H), 3.53 (dt, J = 20. 7,10.1Hz,6H),2.81(s,2H),2.74(d,J=0.6Hz,2H),2.2(d,J=8.1Hz,1H),2.14–1.85(m,2H).

[0282] Example 25

[0283] This embodiment provides a polyboron complex (4CN-BNC-4), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0284] (1) Dissolve 2-hydroxy-4-cyanobenzaldehyde (1n, 1.47 g, 10 mmol) in 80-200 mL of ethanol, add propylenediamine (0.37 g, 5 mmol), and reflux for 18-30 h. The reaction is complete after monitoring by TLC. The reaction solution is cooled to 0-10°C and filtered with a vacuum pump to obtain 1.25 g of a yellow solid, thereby obtaining compound 2n with a yield of 75.3%.

[0285] (2) Compound 2n (332 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 4-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h, and the reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 4-CN-BNC-4489 mg with a yield of 85%.

[0286] Spectral data of 4-CN-BNC-4: ESI-MS (m / z): 575 [M+H] + ;

[0287] 1 H NMR(300MHz,DMSO-d6)δ8.34(s,2H),7.21(d,J=8.6Hz,4H),6.41–6.18(m,6H),3.57(dt,J=20 .6,10.1Hz,6H),2.81(s,2H),2.71(d,J=0.6Hz,2H),2.31(d,J=8.1Hz,1H),2.13–1.82(m,2H).

[0288] Example 26

[0289] This embodiment provides a polyboron complex (4CN-BNC-3), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0290] (1) Dissolve 2-hydroxy-4-cyanobenzaldehyde (1n, 1.47 g, 10 mmol) in 80-200 mL of ethanol, add propylene diamine (0.37 g, 5 mmol), and reflux for 18-30 h. The reaction is complete after monitoring by TLC. The reaction solution is cooled to 0-10°C and filtered with a vacuum pump to obtain 1.35 g of a yellow solid, thereby obtaining compound 2n with a yield of 81.3%.

[0291] (2) Compound 2n (332 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 3-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h, and the reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 480 mg of 4-CN-BNC-3 with a yield of 83.4%.

[0292] Spectral data of 4-CN-BNC-3: ESI-MS (m / z): 575 [M+H] + ;

[0293] 1 H NMR (300MHz, DMSO-d6) δ8.36 (s, 2H), 7.3 (d, J = 8.6Hz, 4H), 6.5–6.15 (m, 6H), 3.55 (dt, J = 20. 7,10.1Hz,6H),2.83(s,2H),2.72(d,J=0.6Hz,2H),2.2(d,J=8.1Hz,1H),2.14–1.85(m,2H).

[0294] Example 27

[0295] This embodiment provides a polyboron complex (4OCH3-BNC-4), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0296] (1) Compound 2-hydroxy-4-methoxybenzaldehyde (1o, 1.52 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.45 g of a yellow solid, compound 2o, with a yield of 84.8%.

[0297] (2) Compound 2o (342 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 4-boronic acid-L-phenylalanine ( 10B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h. The reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 4-OCH3-BNC-4475 mg in a yield of 81.2%.

[0298] Spectral data of 4-OCH3-BNC-4: ESI-MS (m / z): 585 [M+H] + ;

[0299] 1 H NMR (300MHz, DMSO-d6) δ8.3 (s, 2H), 7.2 (d, J = 8.6Hz, 4H), 6.41–6.18 (m, 6H), 3.56 (dt, J = 20. 6,10.1Hz,6H),2.84(s,2H),2.71(d,J=0.6Hz,2H),2.3(d,J=8.1Hz,1H),2.13–1.82(m,2H).

[0300] Example 28

[0301] This embodiment provides a polyboron complex (4OCH3-BNC-3), the structure of which is shown below, and the preparation method thereof comprises the following steps:

[0302] (1) Compound 2-hydroxy-4-methoxybenzaldehyde (1o, 1.5.2 g, 10 mmol) was dissolved in 80-200 mL of ethanol, and propylenediamine (0.37 g, 5 mmol) was added. The mixture was refluxed for 18-30 h. The reaction was monitored by TLC until completion. The reaction solution was cooled to 0-10°C and filtered with a vacuum pump to obtain 1.45 g of a yellow solid, giving compound 2o with a yield of 84.8%.

[0303] (2) Compound 2o (342 mg, 1 mmol) was dissolved in an organic solvent such as acetonitrile, dichloroethane, N,N-dimethylformamide, dimethyl sulfoxide, etc., and 122 mg of boric acid ( 10 B, 2mmol), under nitrogen protection, heated to reflux at 80-100 ° C for 4h, and then added 209mg of 3-boronic acid-L-phenylalanine ( 10 B, 1 mmol), heated under reflux at 80-100 ° C for 18-30 h, and the reaction was monitored by TLC. The reaction solution was cooled and recrystallized to obtain 4-OCH3-BNC-3480 mg in a yield of 82%.

[0304] Spectral data of 4-OCH3-BNC-3: ESI-MS (m / z): 585 [M+H] + ;

[0305] 1H NMR (300MHz, DMSO-d6) δ8.36 (s, 2H), 7.3 (d, J = 8.6Hz, 4H), 6.4–6.15 (m, 6H), 3.55 (dt, J = 20. 7,10.1Hz,6H),2.86(s,2H),2.73(d,J=0.6Hz,2H),2.2(d,J=8.1Hz,1H),2.14–1.82(m,2H).

[0306] Test example

[0307] Test Example 1: Cytotoxicity Experiment

[0308] Human brain glioma cells U87, human liver cancer cells HepG2, human umbilical vein endothelial cells HUVEC, human normal liver cells L02, and mouse breast cancer cells 4T1 were cultured in DMEM cell culture medium containing peptide bovine serum at 37°C in a 5% CO2 incubator. U87 cells, HepG2 cells, HUVEC cells, and 4T1 cells in the logarithmic growth phase were treated with trypsin digestion solution to prepare a concentration of 4×10 5 The cell suspension was added to a 96-well cell culture plate and 200 μL was cultured for 12 hours. After the cells adhered to the wall and grew, the supernatant was removed, and the tissue culture medium of the control group (without drug) and the test group (with drug) was added, and the cells were incubated for 16 hours at 37°C, 5% CO2, and saturated humidity. The 96-well cell culture plate was taken out, and after observing the cell status under an inverted microscope, 20 μL of cck-8 solution was added to each well and the cells were incubated for another 2 hours. The 96-well cell culture plate was placed in a microplate reader for detection. The test results are shown in Figures 1 to 9. The polyboron complex of this test example uses 4OH-BNC-4 of Example 4, 4OH-BNC-3 of Example 10, and 4F-BNC-3 of Example 11.

[0309] Figures 1 to 5 are the cytotoxicity test results of the polyboron complex 4OH-BNC-4 of Example 4 in U87, HepG2, HUVEC, L02, and 4T1 cells.

[0310] FIG6 and FIG7 are the cytotoxicity test results of the polyboron complex 4OH-BNC-3 in Example 10 on L02 and 4T1 cells respectively.

[0311] FIG8 and FIG9 are the results of cytotoxicity tests of the polyboron complex 4F-BNC-3 in Example 11 on L02 and 4T1 cells, respectively.

[0312] As shown in Figures 1 to 9, the polyboron complexes of the present invention have excellent biosafety, especially when the concentration does not exceed 400 μM. These polyboron complexes all show good biocompatibility, laying a foundation for their further biological applications.

[0313] Table 1 shows the relative proliferation rate (RGR) of U87, HepG2, HUVEC, L02, and 4T1 cells under 400 μM polyboron complex conditions.

[0314] Table 1 Relative cell proliferation rate (RGR) measured by CCK-8 colorimetry

[0315] Experimental Example 2: Evaluation of Boron Uptake Ability of Polyboron Complexes in Different Cell Lines

[0316] In order to investigate the enrichment ability of this type of polyboron complex in tumor cells, U87 cells, HepG2 cells, HUVEC cells and 4T1 cells in the logarithmic growth phase were added with appropriate amount of DMEM culture medium (10% fetal bovine serum, 100 U / mL penicillin) to adjust the cell concentration to 1×10 5 Cells were inoculated into 6-well culture plates at 400 μM / ml. After 24 hours of culture, the prepared test drugs (polyboron complex or BPA) were added to a final drug concentration of 300 μM. The cells were placed in a 5% CO2 incubator and cultured at 37°C for 24 hours. The culture medium in the culture dish was removed with a pipette, washed with PBS (3×1 mL), and 1 mL of trypsin was added to the culture dish. The cells were then placed in a 37°C constant temperature CO2 incubator and cultured for 3 minutes. During this period, the cells were observed under a microscope to see if they shrank and rounded. After shrinking and rounding, 1 mL of culture medium was quickly added to terminate the digestion. The attached cells were gently blown to make all the cells fall off from the bottom of the culture dish. The cell suspension was then transferred to a centrifuge tube and diluted. The number of cells in each well was calculated using a hemocytometer. The cell suspension was centrifuged, the supernatant was removed, and PBS was added for washing (3×1 mL). To the washed centrifuge tube containing the cells, 0.5 mL of 0.1% nitric acid and 0.5 mL of 0.1% Triton X-100 were added for digestion. Boron content in the cells was measured using ICP-MS. Based on the cell number in each sample group, the relative uptake efficiency of the polyboron complex relative to BPA in tumor cells and normal cells was calculated. The uptake results are shown in Figures 10 to 13. The polyboron complexes used in this experimental example were Compound A from Example 1, 4OH-BNC-4 from Example 4, 4OH-BNC-3 from Example 10, and 4F-BNC-3 from Example 11.

[0317] Figure 10 shows the relative cellular uptake efficiency of compound A and BPA in HepG2 cells, 4T1 cells and U87 cells, respectively; Figure 11 shows the relative cellular uptake efficiency of 4OH-BNC-4 and BPA in HepG2 cells, 4T1 cells and U87 cells, respectively; Figure 12 shows the relative cellular uptake efficiency of 4OH-BNC-3 and BPA in U87 cells, 4T1 cells and HUVEC cells, respectively; Figure 13 shows the relative cellular uptake efficiency of 4F-BNC-3 and BPA in 4T1 cells and HUVEC cells, respectively.

[0318] Figures 10 through 13 show the relative uptake efficiencies of polyboron complex compounds A, 4OH-BNC-4, 4OH-BNC-3, and 4F-BNC-3 in tumor cells and normal cells, compared to the traditional BNCT drug BPA. Tumor cells significantly increase boron uptake of the polyboron complexes compared to BPA, demonstrating that the compounds of the present invention can be used as BNCT boron drugs and have the potential to kill tumor cells. Furthermore, their neutron capture probabilities upon neutron irradiation are much greater than those of BPA, suggesting that their tumor cell-killing abilities are significantly superior to those of BPA.

[0319] Application Example 1: Evaluation of in vitro activity of BNCT mediated by polyboron complexes

[0320] BNCT experiments were performed using 4T1 cells at the BNCT Center of Xiamen Hongai Hospital. 300 μmol of polyboron complex and BPA were added to the 4T1 cells, respectively. A control group without drug addition was used, and the cells were incubated for 20 hours. After incubation, the cells were washed three times with PBS, trypsinized, and counted. 100,000 cells (1 ml) were transferred to a 1.5 ml centrifuge tube and irradiated with a specific neutron flux. The cells were divided into three groups based on irradiation conditions: one group received 9 minutes of BNCT irradiation at an average neutron flux of 21,309.74 n / cm² / s; one group received 12 minutes of BNCT irradiation at an average neutron flux of 21,274.09 n / cm³ / s; and one group received no irradiation. Irradiation was completed. 4T1 cells (300 cells / well, 2 ml) were then seeded into 6-well plates and cultured in an incubator for 7 days, with fresh culture medium replaced every 48 hours. After 7 days, the culture medium was removed, the plates were gently washed with PBS, fixed with 4% paraformaldehyde (1 ml) for 30-60 minutes, washed once with PBS, stained with crystal violet (1 ml) for 10-20 minutes, washed several times with PBS, dried, and photographed. The experimental results are detailed in Figures 14 to 16. The polyboron complexes used in this application test example were 4OH-BNC-4 from Example 4, 4OH-BNC-3 from Example 10, and 4F-BNC-3 from Example 11.

[0321] Figure 14 shows images of cells in different drug groups after irradiation under different conditions in this application example. Figure 15 shows the number of cell clones formed. Figure 16 shows the colony formation efficiency of the two irradiation groups.

[0322] As shown in Figures 14 to 16, under the same neutron fluence, we can see from the figures that the polyboron complexes 4OH-BNC-4, 4OH-BNC-3, and 4F-BNC-3 significantly reduced the colony formation rate of 4T1 cells under neutron irradiation, further demonstrating that the BNCT effect mediated by 4OH-BNC-4, 4OH-BNC-3, and 4F-BNC-3 has a significant killing effect on 4T1 cells, and the tumor cell killing effect of the polyboron complex is stronger than that of BPA. This shows that the polyboron complex of the present invention can be used as a boron drug for BNCT and has great potential in tumor treatment.

[0323] Test Example 3: UV measurement

[0324] The polyboron complex of the present invention was subjected to UV measurement. The polyboron complex mother solution used in the UV measurement experiment consisted of a phosphate buffer solution containing 10% NaOH (500 mM). The mother solution was prepared into a 20 mM standard stock solution. The polyboron complex concentration used for UV absorption spectroscopy was 50 μM, and the absorption spectrum was set between 300 and 500 nm.

[0325] Compounds tested by UV spectroscopy: 4OH-BNC-4 of Example 4, 4H-BNC-4 of Example 12, 4CH3-BNC-4 of Example 18, and 4Cl-BNC-4 of Example 20. The UV spectroscopy results are shown in FIG17 .

[0326] Test Example 4: Fluorescence measurement

[0327] The fluorescence properties of the polyboron complex of the present invention were further studied. The polyboron complex mother solution solvent system used in the fluorescence property determination experiment was a phosphate buffer system containing 10% NaOH (500 mM). The mother solution was configured into a 20 mM standard stock solution. The concentrations of the polyboron complex selected for fluorescence emission spectrum determination were 50 μM, 100 μM, and 200 μM. The excitation wavelength was 310 nm or 405 nm, and the detection range of the fluorescence emission spectrum was set to 400 to 700 nm. During detection, the excitation slit width of the fluorescence spectrophotometer was 10, and the emission slit width was 5.

[0328] Compounds used for fluorescence measurement: BNC-4 series compounds (4CH3-BNC-4 of Example 18, 4H-BNC-4 of Example 12, 4OH-BNC-4 of Example 4, 4Cl-BNC-4 of Example 20), and BNC-3 series compounds (4CH3-BNC-3 of Example 19, 4H-BNC-3 of Example 13, 4NO2-BNC-3 of Example 24, 4CN-BNC-3 of Example 26, 4F-BNC-3 of Example 11, 4OH-BNC-3 of Example 10). The fluorescence measurement results are shown in Figures 18 and 19.

[0329] Figure 18 shows the fluorescence measurement results of the BNC-4 series of compounds, indicating that the BNC-4 series of compounds have good fluorescence properties at the in vitro level; Figure 19 shows the fluorescence measurement results of the BNC-3 series of compounds, indicating that these compounds also have good fluorescence properties. It can be seen that the polyboron complexes of the present invention have potential fluorescence imaging properties and have application prospects for integrated diagnosis and treatment. The fluorescence imaging properties of the boron drugs of the present invention enable researchers to more accurately observe and evaluate the uptake of boron drugs in cells, thereby helping researchers to observe and verify the targeting of boron drugs at the molecular level, ensuring that the drugs can accurately reach and remain in tumor cells, realizing the integrated diagnosis and treatment of BNCT boron drugs, and thus optimizing the therapeutic effect of BNCT.

[0330] Test Example 5: Cytotoxicity test / cell safety determination

[0331] Using an equal mass of fructose as a cosolvent, 10% NaOH (500mM) phosphate buffer was used to prepare a 20mM stock solution of polyboron complexes, and gradient dilution was performed to different concentrations to investigate the survival rate of cells at different drug concentrations. Human brain glioma cells U87, human triple-negative breast cancer cells MDA-MB-468, and human pancreatic cancer cells PANC-1 were cultured in DMEM cell culture medium containing fetal bovine serum and cultured at 37°C in a 5% CO2 incubator. U87 cells, MDA-MB-468 cells, and PANC-1 cells in the logarithmic growth phase were treated with trypsin digestion solution to prepare a concentration of 4×10 5 200 μL of cell suspension was added to a 96-well cell culture plate and cultured for 12 hours. After the cells adhered to the wall and grew, the supernatant was removed and added to the culture medium of the control group (no drug, i.e., drug concentration was 0) and the test groups (with drug) at different concentrations, and incubated for 24 hours at 37°C, 5% CO2, and saturated humidity. The 96-well cell culture plate was removed, and the cell status was observed under an inverted microscope. 20 μL of CCK-8 solution was added to each well and incubated for another 2 hours. The 96-well cell culture plate was placed in a microplate reader for detection. The polyboron complex drugs of this test example include the BNC-4 series of compounds (4H-BNC-4 of Example 12, 4OH-BNC-4 of Example 4, and 4CH3-BNC-4 of Example 18), and the BNC-3 series of compounds (4OH-BNC-3 of Example 10, 4H-BNC-3 of Example 13, 4CH3-BNC-3 of Example 19, 4F-BNC-3 of Example 11, and 4CN-BNC-3 of Example 26). Figures 20 to 23 show the cytotoxicity test results of the polyboron complexes of the present invention. Specifically, the drug concentration of this test example can be shown in Figures 20 to 23. For example, the drug concentration can be 0.2mM, 0.4mM, 0.6mM, 0.8mM, 1mM, or 50μM, 100μM, 200μM, 300μM, 400μM, 500μM, 600μM, 700μM, 800μM, 1000μM.

[0332] Figure 20 shows the results of the cytotoxicity test of the BNC-4 series of polyboron complexes on U87 cells. Figures 21, 22 and 23 show the results of the cytotoxicity test of the BNC-3 series of polyboron complexes on U87, PANC-1 and MDA-MB-468 cells, respectively.

[0333] As shown in Figures 20 to 23 , the polyboron complexes have excellent safety. In particular, at concentrations below 800 μM, the polyboron complexes of the present invention exhibit good biocompatibility, laying the foundation for their further biological applications.

[0334] Table 2 shows the relative cell proliferation rate (RGR) of U87, PANC-1 and MDA-MB-468 cells under the condition of 800 μM polyboron complexes (BNC-3 series).

[0335] Table 2 Relative cell proliferation rate (RGR) measured by CCK-8 colorimetry

[0336] Experimental Example 6: Cellular uptake experiment

[0337] In order to further investigate the enrichment ability of polyboron complexes in humanized tumor cells, the uptake of polyboron complexes by various tumor cells was studied.

[0338] U87 cells, MDA-MB-468 cells and PANC-1 cells in the logarithmic growth phase were taken and added with appropriate amount of DMEM culture medium (10% fetal bovine serum, 100 U / mL penicillin) to adjust the cell concentration to 1×10 5The cells were inoculated into a 6-well culture plate and incubated for 24 hours. Then, an equal amount of fructose was used as a cosolvent, and a 20 mM stock solution of polyboron complex and BPA were prepared in 10% NaOH (500 mM) phosphate buffer. Each solution was diluted to 600 μM with DMEM and added to the adherent cells. The cells were then placed in a 5% CO2 incubator and incubated for 4 hours at 37°C. The culture medium was removed with a pipette, and the cells were washed with PBS (3 × 1 mL). 1 mL of trypsin was added to the culture dish, and the cells were then incubated in a 37°C constant temperature CO2 incubator for 3 minutes. During this time, the cells were observed under a microscope to see if they shrank or rounded. If they did, 1 mL of culture medium was quickly added to terminate the digestion. The adherent cells were gently pipetted to detach from the bottom of the culture dish. The cell suspension was then transferred to a centrifuge tube, diluted, and counted using a hemocytometer to calculate the number of cells per well. The cell suspension was centrifuged, the supernatant removed, and washed with PBS (3 × 1 mL). To the washed centrifuge tube containing the cells, 0.5 mL of 0.1% nitric acid and 0.5 mL of 0.1% Triton X-100 were added for digestion. Boron content in the cells was measured using ICP-MS. Boron uptake by polyboron complexes and BPA in tumor cells was calculated based on the number of cells in each sample group. The uptake results are shown in Figures 24 and 25. The polyboron complexes used in this experimental example include the BNC-4 series (4H-BNC-4 in Example 12, 4OH-BNC-4 in Example 4, and 4CH3-BNC-4 in Example 18), and the BNC-3 series (4H-BNC-3 in Example 13, 4OH-BNC-3 in Example 10, 4F-BNC-3 in Example 11, 4CH3-BNC-3 in Example 19, and 4CN-BNC-3 in Example 26).

[0339] Figure 24 shows the boron uptake of BNC-4 series polyboron complexes and the traditional BNCT drug BPA in U87 tumor cells. Figure 25 shows the boron uptake of BNC-3 series polyboron complexes and BPA in U87, MDA-MB-468 and PANC-1 tumor cells.

[0340] The results show that the tumor cells have an excellent boron uptake capacity for the polyboron complex of the present invention, indicating that the polyboron complex of the present invention has excellent tumor cell killing ability when applied in the field of BNCT.

[0341] Furthermore, the compounds of this invention significantly increase boron uptake in tumor cells compared to the traditional BNCT drug BPA, indicating that the compounds of this invention have a much higher probability of neutron capture upon neutron irradiation than BPA. Consequently, it is inferred that their tumor cell-killing ability is far superior to that of BPA. Clearly, this invention has excellent application prospects in the field of BNCT.

[0342] Application Example 2: Cell Therapeutic Effect Evaluation

[0343] To further investigate the cellular efficacy of polyboron complexes in humanized tumor cells, BNCT experiments were performed using U87 cells at the BNCT Center of Xiamen Hongai Hospital.

[0344] Using equal mass of fructose as a cosolvent, 10% NaOH (500mM) phosphate buffer was used to prepare 20mM of polyboron complex mother solution and BPA. 600μM polyboron complex and BPA were added to U87 cells as treatment groups, and the group without drug addition was used as the control group (Control) and incubated for 4h. After the culture, the cells were washed 3 times with PBS, digested with trypsin, counted, and 100,000 cells in 1ml were transferred to a 1.5ml centrifuge tube. A certain neutron dose intensity was selected for BNCT irradiation. According to the irradiation conditions, the cells were divided into two groups. One group selected an average neutron flux of 16059762n / cm 2 / s, irradiation time was 9 minutes (irradiation); one group was without irradiation (w / oirradiation). Irradiation was completed. U87 cells (600 cells / well, 2 mL) were then seeded into a 6-well plate and placed in an incubator for 7 days. Fresh culture medium was replaced every 48 hours. After 7 days, the culture medium was removed and gently washed with PBS. 4% paraformaldehyde (1 ml) was used to fix the cells for 30-60 minutes, washed once with PBS, and crystal violet (1 ml) was added for staining for 10-20 minutes. The cells were washed several times with PBS, dried and photographed. The experimental results are shown in Figures 26 and 27. The polyboron complexes of this experimental example: 4CN-BNC-3 of Example 26, 4CH3-BNC-3 of Example 19, and 4H-BNC-4 of Example 12.

[0345] Figure 26 shows the cell results of different drug groups under different irradiation conditions in this application example. The left figure in Figure 27 shows the cell number in this application example; the right figure shows the inhibition rate of cell clone formation in this application example.

[0346] As shown in Figures 26 and 27, under the same neutron fluence irradiation, the polyboron complexes of the present invention (4CN-BNC-3, 4CH3-BNC-3, 4H-BNC-4) significantly reduced the colony formation rate of U87 cells after neutron irradiation, and the cell efficacy of 4CH3-BNC-3 and 4H-BNC-4 of the present invention was significantly better than that of BPA, further demonstrating that the polyboron complexes of the present invention have a strong tumor cell killing effect when applied to BNCT. In summary, the polyboron complexes of the present invention have excellent application prospects as BNCT boron drugs.

[0347] Application Example 3: Study on Boron Distribution at the Living Level

[0348] Based on the results obtained at the cellular level, a U87 xenograft tumor model was constructed. Tumor-bearing nude mice were randomly divided into five groups, with three mice in each group. A 27.12 mg / ml stock solution of the polyboron complex was prepared in 10% NaOH (500 mM) phosphate buffer using an equal mass of fructose as a cosolvent, and the mice were administered via tail vein injection at a dose of 271.2 mg / kg (0.5 mmol / kg). A control group received an equal molar amount of BPA (0.5 mmol / kg) via the tail vein. At various time points (0.5 h, 1 h, 2 h, 4 h, 8 h) or (0.5 h, 1 h, 2 h, 4 h) after administration, orbital blood was drawn and the mice were sacrificed. Tumors were removed, and the tumor tissue and blood were digested using a microwave digester to obtain sample extracts. The boron content of each extract was analyzed by ICP-MS. The results are shown in Figure 28. Using BPA as a reference, the distribution characteristics of the polyboron complex in the tumor tissue and blood of tumor-bearing mice at a reasonable dosage were investigated, and the T / B ratio was calculated. The results are shown in Figure 29. The polyboron complex in this test example is 4CH3-BNC-3 of Example 19.

[0349] Figure 28 shows the boron uptake levels of 4CH3-BNC-3 and BPA in tumor tissue and blood of U87 mice, respectively. Figure 29 shows the ratio of boron concentration (T / B) in tumor tissue and blood of 4CH3-BNC-3 and BPA in U87 mice, respectively.

[0350] As shown in Figure 28, the polyboron complex 4CH3-BNC-3 of the present invention exhibited approximately 8 μg / g tumor boron uptake at 0.5 h and approximately 3 μg / g at 4 h. In contrast, BPA exhibited approximately 3.2 μg / g tumor boron uptake at 0.5 h and approximately 0.8 μg / g at 4 h. This significantly improved the boron uptake of the polyboron complex of the present invention compared to BPA, demonstrating its excellent application prospects.

[0351] As shown in Figure 29, the ratio of boron concentration in tumor tissue to blood (T / B) of mice in the 4CH3-BNC-3 treatment group and the BPA treatment group shows that the T / B ratio of the polyboron complex at 4 h is about 1.5, while the T / B ratio of BPA at 4 h is about 1.2. This shows that the ratio of boron concentration in tumor tissue to blood of the polyboron complex of the present invention is also higher than that of BPA.

[0352] In summary, the polyboron complex of the present invention is a BNCT drug with application potential, has excellent tumor uptake effect, can help B-10 effectively enrich and retain in cancer cells, and is beneficial to the implementation of BNCT.

[0353] The above description is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A polyboron complex or a stereoisomer, deuterated product or pharmaceutically acceptable salt thereof, wherein: The polyboron complex structure is shown in the following formula (I): R1 and R2 are each independently selected from: H, F, Cl, Br, I, -OH, -R'OH, alkyl, alkoxy, amino, nitro, cyano, alkylthio, alkenyl, alkynyl, cycloalkyl, cycloalkyloxy, cycloalkylthio, acyl, ester, amide, aryl, heterocyclyl, heteroaryl, heterocycloalkyl, monoalkylamino or dialkylamino; R' is selected from substituted or unsubstituted alkylene groups having 1 to 6 carbon atoms; the substituted groups are selected from halogen, hydroxyl, amino, and nitro; R3 is R5 is selected from H, F, Cl, Br, I, hydroxyl or dihydroxyboryl; a, b are each independently selected from 0, 1, 2, 3 or 4; x is selected from 0, 1, 2, 3 or 4; n is selected from 0, 1 or 2; The above * is the connection site.

2. The polyboron complex according to claim 1 or its stereoisomer, deuterated substance or pharmaceutically acceptable salt, wherein: The polyboron complex structure is shown in the following formula (II):

3. The polyboron complex according to claim 1 or 2, or a stereoisomer, a deuterated substance or a pharmaceutically acceptable salt thereof, wherein: R1 and R2 are each independently selected from H, F, Cl, Br, I, -OH, -R'OH, nitro, cyano, C 1-10 Alkyl or C 1-10 Alkoxy.

4. The polyboron complex according to claim 1 or 2, or a stereoisomer, a deuterated substance or a pharmaceutically acceptable salt thereof, wherein: R1 and R2 are each independently selected from F, Cl, Br, I, -OH, -R'OH, nitro, cyano, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, -CH(CH3)CH2CH2CH3, -CH2CH(CH3)CH2CH3, -CH2CH2CH(CH3)2, -CH(C2H5)CH2CH3, -C(CH3)2CH2CH3, -CH(CH3)CH(CH3)2, -CH2C(CH3)3, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy or tert-butoxy.

5. The polyboron complex according to claim 1 or 2, or a stereoisomer, a deuterated substance or a pharmaceutically acceptable salt thereof, wherein: R1 and R2 are each independently selected from H, F, Cl, Br, I, -OH, -R'OH, nitro, cyano, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, -CH(CH3)CH2CH2CH3, -CH2CH(CH3)CH2CH3, -CH2CH2CH(CH3)2, -CH(C2H5)CH2CH3, -C(CH3)2CH2CH3, -CH(CH3)CH(CH3)2, -CH2C(CH3)3, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy or tert-butoxy.

6. The polyboron complex according to claim 1 or 2, or a stereoisomer, a deuterated substance or a pharmaceutically acceptable salt thereof, wherein: R1 and R2 are each independently selected from H, F, Cl, Br, I, -OH, -R'OH, C 1-3 Alkyl or C 1-3 Alkoxy.

7. The polyboron complex according to claim 2 or its stereoisomer, deuterated substance or pharmaceutically acceptable salt, wherein: for Preferably 8. The polyboron complex according to claim 2 or 7, or a stereoisomer, a deuterated substance or a pharmaceutically acceptable salt thereof, wherein: R5 is selected from H, F, Cl, Br, I or hydroxyl, preferably H; x is selected from 0, 1, 2, 3 or 4, preferably 0 or 1.

9. The polyboron complex according to claim 2 or its stereoisomer, deuterated substance or pharmaceutically acceptable salt, wherein: R1 and R2 are each independently selected from H, F, Cl, Br, I, -OH, -R'OH, methyl, methoxy or ethoxy; R' is selected from substituted or unsubstituted alkylene with 1 to 3 carbon atoms; the substituted group is selected from halogen and hydroxyl; R5 is selected from H, F, Cl, Br, I, hydroxyl; a, b are each independently selected from 0, 1 or 2; x is selected from 0, 1, 2, 3 or 4; n is selected from 0, 1 or 2.

10. The polyboron complex according to claim 1 or its stereoisomer, deuterated substance or pharmaceutically acceptable salt, wherein: Selected from R1 and R2 are each independently selected from H or methyl, preferably, R1 and R2 are each independently methyl; n is 1; a and b are each independently 0 or 1, preferably, a and b are each independently 1.

11. The polyboron complex according to claim 2 or 7, or a stereoisomer, a deuterated substance or a pharmaceutically acceptable salt thereof, wherein for 12. The polyboron complex according to claim 1 or its stereoisomer, deuterated substance or pharmaceutically acceptable salt, wherein: R1 and R2 are the same, a and b are the same, and R1 and R2 are bilaterally symmetrical with A-A' of the following formula (I) as the symmetry axis:

13. The polyboron complex according to claim 1 or 2, or a stereoisomer, a deuterated substance or a pharmaceutically acceptable salt thereof, wherein: The polyboron complex is selected from one of the following structures:

14. The polyboron complex according to claim 1 or 2, or a stereoisomer, a deuterated substance or a pharmaceutically acceptable salt thereof, wherein: At least one of the Bs in the polyboron complex is 10 B; Preferably, all B of the polyboron complex is 10 B.

15. A pharmaceutical composition, wherein: The pharmaceutical composition contains the polyboron complex according to any one of claims 1 to 14 or its stereoisomer, deuterated substance or pharmaceutically acceptable salt, and a pharmaceutically acceptable carrier.

16. The pharmaceutical composition according to claim 15, wherein The pharmaceutical composition further comprises a cosolvent; the cosolvent comprises galactose or fructose; and / or the cosolvent is prepared using a phosphate buffer solution of NaOH.

17. The pharmaceutical composition according to claim 15, wherein The pharmaceutical composition also contains galactose. Based on the total weight of the pharmaceutical composition being 100%, the weight percentage of the polyboron complex or its stereoisomers, deuterated substances or pharmaceutically acceptable salts is 0.05%-90%, and the weight percentage of the galactose is 40%-60%.

18. Use of the polyboron complex according to any one of claims 1 to 14 or its stereoisomer, deuterated product or pharmaceutically acceptable salt, or the pharmaceutical composition according to any one of claims 15 to 17 in the preparation of anti-tumor drugs.

19. The use according to claim 18, wherein: The tumor is selected from glioma, pancreatic cancer, triple-negative breast cancer, liver cancer, melanoma, head and neck tumor, brain tumor, meningioma, pleural mesothelioma, lung cancer, osteosarcoma, cervical cancer or bladder cancer.

20. The use according to claim 18, wherein: The tumor is a central nervous system tumor or breast cancer.

21. The use according to claim 18, wherein: The anti-tumor drug is an anti-tumor drug used under neutron irradiation conditions.

22. A method for preparing a polyboron complex or its stereoisomers, deuterated products or pharmaceutically acceptable salts, wherein: The method comprises the steps of preparing the polyboron complex using compound (1) and compound (2) as raw materials: R1 and R2 are each independently selected from: H, F, Cl, Br, I, -OH, -R'OH, alkyl, alkoxy, amino, nitro, cyano, alkylthio, alkenyl, alkynyl, cycloalkyl, cycloalkyloxy, cycloalkylthio, acyl, ester, amide, aryl, heterocyclic, heteroaryl, heterocycloalkyl, monoalkylamino or dialkylamino; R' is selected from substituted or unsubstituted alkylene with 1 to 6 carbon atoms; the substituted group is selected from halogen, hydroxyl, amino, nitro; R3 is R5 is selected from H, F, Cl, Br, I, hydroxyl or dihydroxyboryl; x is selected from 0, 1, 2, 3 or 4; a, b are each independently selected from 0, 1, 2, 3 or 4; n is selected from 0, 1 or 2; The above * is the connection site.

23. The preparation method according to claim 22, wherein: The method further comprises the step of preparing a compound of formula (1) using a compound of formula (3) and boric acid as raw materials:

24. The preparation method according to claim 23, wherein: The method further comprises the step of preparing a compound of formula (3) using a compound of formula (4), a compound of formula (4') and a compound of formula (5) as raw materials:

25. The preparation method according to claim 24, wherein: The compound of formula (4) and the compound of formula (4') have the same structure.

26. The method for preparing the polyboron complex or its stereoisomer, deuterated product or pharmaceutically acceptable salt according to claim 22, wherein: for

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