Application of IR-780-labeled dodecaborane derivatives in the preparation of drugs for tumor treatment

Abstract

The present invention discloses the application of an R-780-labeled dodecaborane derivative in the preparation of a drug for tumor treatment. The derivative comprises an IR-780 fluorescent probe structure and a dodecaborane structure. In the synthesis of the derivative, the IR-780 fluorescent probe structure and the dodecaborane structure are directly connected through a thioether bond in BSH, or are connected through a series of spacers with different lengths. The partial structure of the fluorescent probe in this compound proposed by the present invention has a high photothermal conversion efficiency and can achieve the effect of a fluorescent probe. A large amount of boron elements contained in the dodecaborane structure can be used for BNCT combined treatment by using the <supgt;10< / supgt;B-enriched product of <supgt;10< / supgt;B-enriched mercaptododecaborate. Moreover, the preparation process of this compound is simple, reliable and easy to implement.

Description

Technical Field

[0001] The present invention relates to the fields of chemical technology and medicine, and relates to the synthesis of pharmaceutical compounds for tumor photothermal therapy (PTT) or boron neutron capture therapy (BNCT) and the combined treatment of the two methods. Specifically, it relates to the reaction of the heptamethine cyanine fluorescent dye IR-780 with a series of mercaptododecaborates (BSH), and the methods for separating, purifying the products and their medical applications. Background Art

[0002] Malignant tumors have become one of the deadliest diseases today, and the exploration of treatment methods for them has never stopped. Currently, common tumor treatment methods include surgical resection, chemotherapy, radiotherapy, and immunotherapy, etc. Clinically, surgical resection of tumor tissues is usually selected, and then various methods are combined for lesion, metastasis, lymph node dissection, etc. to achieve the best treatment effect. Photothermal therapy (PTT) and boron neutron capture therapy (BNCT) are relatively new technologies among various tumor treatment methods, and there have been years of research accumulations and they are gradually being promoted and applied clinically.

[0003] Photothermal therapy is a treatment method that injects materials with high photothermal conversion efficiency into the human body. Through targeted recognition, these materials aggregate near tumor tissues and convert light energy into heat energy under the irradiation of an external light source (usually near-infrared light) to kill cancer cells. Among them, photosensitizers with high photothermal conversion efficiency are the key to PTT. Those that have been studied more include noble metal nanoparticles such as gold, silver, platinum, etc.; carbon group nanomaterials such as graphene, carbon nanorods, etc.; compounds composed of metal elements and non-metal elements such as copper sulfide, zinc sulfide, etc.; organic dyes such as indocyanine green, Prussian blue series dyes, and various derivatives of the above materials. 2-(2-(2-chloro-3-(2-(3,3-dimethyl-1-propylindol-2-ylidene)ethylidene)cyclohex-1-en-1-yl)vinyl)-3,3-dimethyl-1-propylindol-1-ium iodide (IR-780) is one of them, belonging to the indocyanine green series dyes. It has a maximum absorption at a wavelength of 750-830 nm and converts it into heat, raising the temperature of tumor tissues to kill tumor cells. The external light source used in PTT is mainly near-infrared light, and even infrared light is expected to be used, aiming to obtain a greater tissue penetration depth while reducing the direct damage of light source irradiation to tissues. However, limited by the maximum absorption wavelength of photosensitizers, currently, the main research is still on near-infrared light, and it is often only effective for superficial tumors that can be directly penetrated by near-infrared light, such as epithelial cell carcinoma. In addition, in order to obtain better treatment effects, PTT often requires multiple and repeated irradiations to effectively kill tumor cells.

[0004] Boron neutron capture therapy is a cell-scale targeted binary radiotherapy method. The principle of BNCT to kill tumor cells is that the non-radioactive isotope 10 B undergoes a nuclear fission reaction after being bombarded by thermal neutrons to generate an alpha particle and a 7 Li atom. The alpha particle produces a lethal effect on cells, but its action range is only the size of one cell. Therefore, it can effectively kill cancer cells while hardly damaging the surrounding normal tissues. The necessary conditions for BNCT are neutron irradiation and 10 B atoms that can be enriched in tumor cells in sufficient quantities. Compounds containing 10 B atoms are called boron carriers or boron drugs. Currently, only two boron drugs, 4-dihydroxyboron-L-phenylalanine (L-BPA) and sodium undecahydrododecaborane mercaptide (BSH), have been approved for clinical use. Currently, the BNCT method has carried out clinical research on superficial tumors such as melanoma, glioma, and head and neck tumors. However, obtaining more effective boron drugs is still the key for this method to play its role.

[0005] Based on the IR-780 dye, Chinese invention patents CN111004624A and CN113476602A disclose a novel near-infrared fluorescent probe molecule. By connecting two molecules of IR-780 with one molecule of 1,2-diphenyl-1,2-bis(4-hydroxyphenyl)ethylene, a compound combining the IR-780 and tetraphenylethylene (TPE) structures is formed, which is used for photothermal therapy and photodynamic therapy and has the function of integrated diagnosis and treatment. Chinese invention patent ZL201510313016 discloses a near-infrared fluorescent compound based on a cyanine dye skeleton. By successively combining IR-780 with piperazine and 4-chloro-7-nitro-2,1,3-benzoxadiazole, the obtained compound can be used for near-infrared fluorescence recognition of hydrogen sulfide molecules. Chinese invention patent publication CN102491930A discloses a pH-responsive fluorescent probe molecule with IR-780 as the parent, which is combined with isopropylamine, benzylamine, methyl ethylamine, N-methylaniline, ethylenediamine, hexamethylenediamine, p-phenylenediamine, etc., and has a high fluorescence quantum yield. Chinese invention patent ZL201410289402 discloses a near-infrared mesoporous silica fluorescent nanoprobe formed by combining IR-780 with mesoporous silica, which has good biocompatibility. Chinese invention patent ZL201510312670 discloses a fluorescent probe molecule obtained by combining IR-780 with a 1,8-naphthalimide structure, which can selectively recognize glutathione (GSH). Chinese invention patent ZL201810213918 discloses a drug-loaded micelle obtained by combining IR-780 with chitosan stearic acid and encapsulating doxorubicin drugs, which can target tumor cells and rapidly release drugs under near-infrared light, inducing apoptosis of tumor cells and improving the anti-tumor treatment effect. However, the above modifications and modifications of IR-780 only involve fluorescent probes or photothermal therapy, etc., and do not connect boron-containing compound structures and are not used for BNCT or PTT-BCNT treatment.

[0006] In the research field of boron carriers for BNCT, Li Jiyuan et al. summarized the development process and existing research types of boron carriers in the past few decades in "An Unpopular Direction Approaching Dawn: A Brief Introduction to the Development Process of Boron Carriers" (Chinese Science · Chemistry, 2020, 50(10): 1296), including boron-containing small molecules, boron-containing biological macromolecules, boron-containing nanodrugs, etc. Chinese invention patents CN109942608A and CN109988187A respectively disclose a nitroimidazole-containing polyboron phenylalanine compound and a carborane-containing phenylalanine compound. Both of these two molecules can be used for BNCT treatment, but do not involve diagnosis and treatment or photothermal therapy. Chinese invention patent CN111204736A discloses a boron-containing carbon quantum dot. Since the quantum dot has fluorescence emission properties in vivo and in vitro, it can be used for BNCT treatment and fluorescence diagnosis, but does not involve photothermal therapy. Chinese invention patents CN1988848A and CN1968705A both disclose a carborane-containing 5,10,15,20-tetraphenylporphyrin compound, which can be used for BNCT treatment and photodynamic therapy (PDT), but this molecule has no fluorescence emission property and does not involve fluorescence diagnosis and photothermal therapy.

[0007] In existing research, to reduce side effects and radiation risks, BNCT usually adopts a one-time irradiation treatment method, while PTT often requires multiple repeated light irradiation treatments due to limited photothermal effects. The combined treatment of the two methods may first kill a large number of cancer cells through the BNCT method, and then continue to clean up the remaining lesions through repeated PTT treatments, or first use the PTT method to limit the growth of tumor tissues during the tumor stage, and then use the BNCT method to kill the tumor tissues, so as to obtain better treatment effects. However, in the reported boron carriers in the known BNCT field, no boron carrier obtained by combining a boron-containing compound, especially the BSH structure, with the IR-780 fluorescent molecule and used for PTT or BNCT and the combined treatment of the two methods has been seen.

[0008] Therefore, how to solve the above problems and obtain a tumor diagnosis and treatment drug that combines a boron-containing element with the IR-780 fluorescent molecule and is used for PTT or BNCT and the combined treatment of the two methods is of great significance. Summary of the Invention

[0009] The object of the present invention is to provide a compound that can be used for PTT, BNCT and PTT-BNCT combined treatment. The compound contains a boron element and can become a boron carrier in BNCT. At the same time, the compound has a high photothermal conversion efficiency and is also a photothermal conversion agent in PTT. Moreover, this type of compound can also be used as a tumor fluorescence probe to realize the combination of imaging detection and treatment preparation.

[0010] To this end, the following technical solutions are provided:

[0011] An IR-780 fluorescent probe-labeled dodecaborane derivative, comprising an IR-780 fluorescent probe structure and a dodecaborane structure, and its structural formula is shown as follows:

[0012]

[0013] Preferably, the IR-780 fluorescent probe structure in the derivative is the residue after the reaction of the fluorescent probe molecule IR-780. Except for the elimination of one chlorine atom, other structures are retained and connected to other partial structures by eliminating the chlorine atom;

[0014] The dodecaborane structure is derived from the residue after the reaction of mercaptododecaborate (BSH). The reaction occurs on the mercapto group connected to the dodecaborane and is connected to other structures by eliminating the H atom on the mercapto group.

[0015] Preferably, the dodecaborane structure is derived from mercaptododecaborate (BSH), and mercaptododecaborane exists in the form of a divalent anion, and the corresponding cation is an alkali metal cation including lithium (Li + ) sodium (Na + ) potassium (K + ) rubidium (Rb + ) cesium (Cs + ) or quaternary ammonium salt (NH 4 + ) and their mixtures.

[0016] Preferably, the IR-780 fluorescent probe structure and the dodecaborane structure in the derivative are directly connected through the thioether bond in BSH, or are connected through a series of spacers with different lengths.

[0017] Preferably, when the IR-780 fluorescent probe structure and the dodecaborane structure are directly connected through the thioether bond in BSH, the synthesis reaction is completed in one step;

[0018] After the reaction, the end point is confirmed by thin-layer chromatography, and then separated and purified by dialysis, column chromatography or preparative liquid chromatography separation methods. Then the product is obtained as a solid finished product after vacuum drying or freeze drying;

[0019] The theoretical molar ratio between the two raw material reactants of the IR-780 fluorescent probe structure and the dodecaborane structure is 1:1.

[0020] Preferably, when the IR-780 fluorescent probe structure and the dodecaborane structure are connected by a spacer, the spacer is a saturated alkane structure with two methylene groups, that is, n = 1 in the structural formula; or a polyether structure, that is, n = 2, 3, 4,......, 20 and their mixtures in the structural formula, but n does not exceed 20 at most.

[0021] Preferably, when the IR-780 fluorescent probe structure and the dodecaborane structure are connected by a spacer, the reactants constituting the spacer structure are the reaction residues of α, ω-haloalcohols, including 2-haloethanol (n = 0), 2-(2-haloethoxy)ethanol (n = 1), 2-[2-(2-haloethoxy)ethoxy]ethanol (n = 2), 2-[2-[2-(2-haloethoxy)ethoxy]ethoxy]ethanol (n = 3), 2-[2-[2-[2-(2-haloethoxy)ethoxy]ethoxy]ethoxy]ethanol (n = 4), α-hydroxy-ω-halopolyethylene glycol (5 ≤ n ≤ 20) and their mixtures;

[0022] The halogen therein includes fluorine (F), chlorine (Cl), bromine (Br) or iodine (I) and mixtures of different haloalcohols.

[0023] Preferably, when the IR-780 fluorescent probe structure and the dodecaborane structure are connected by a spacer, the synthesis reaction is completed in two steps:

[0024] After the reaction, the end point is confirmed by thin layer chromatography, and then separated and purified by dialysis, column chromatography or preparative liquid chromatography separation method. Then the product is vacuum dried or freeze dried to obtain the finished solid product;

[0025] In the first step reaction, the theoretical molar ratio between BSH and α, ω-haloalcohol is 1:1, but in the actual reaction, α, ω-haloalcohol is in relative excess, and the available excess ratio is 10 - 1000%;

[0026] In the second step reaction, the theoretical molar ratio between the intermediate product generated in the previous step and IR-780 is 1:1, but in the actual reaction, IR-780 is in relative excess, and the available excess ratio is 10 - 100%.

[0027] Preferably, the solvents in the reaction include but are not limited to water, pentane, n-hexane, n-octane, n-heptane, cyclohexane, benzene, toluene, ethylbenzene, xylene, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, acetonitrile, ether, ethyl acetate, butyl acetate, tetrahydrofuran, ethylene glycol dimethyl ether, 1,4-dioxane, acetone, butanone, cyclohexanone, N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and their mixtures;

[0028] The bases in the reaction include, but are not limited to, sodium hydroxide, potassium hydroxide, sodium methoxide, sodium ethoxide, triethylamine, triethylenediamine, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]-5-nonene (DBN), pyridine, 4-dimethylaminopyridine (DMAP), N-methylmorpholine, tetramethylethylenediamine, tetramethylguanidine (TMG), and mixtures thereof.

[0029] Preferably, the application of the IR-780 fluorescent probe-labeled dodecaborane derivative in the preparation of drugs for tumor treatment.

[0030] The present invention has at least the following advantages:

[0031] (1) The IR-780 fluorescent probe-labeled dodecaborane derivative proposed by the present invention is obtained by reacting an IR-780 fluorescent dye molecule with a series of mercapto dodecaboranes (BSH) or further connecting a spacer structure between the two and linking them by a covalent bond, obtaining a series of tumor diagnosis and treatment drugs that can be used for PTT, BNCT, and PTT-BNCT combined treatment. Its synthesis process is simple and reliable and is easy to implement.

[0032] (2) The fluorescent probe part structure in this compound has a high photothermal conversion efficiency and can achieve the effect of a fluorescent probe. A large amount of boron element contained in the dodecaborane structure can be used by 10 B-enriched mercapto dodecaborate 10 B-enriched products for BNCT combined treatment.

[0033] (3) The compounds proposed by the present invention have not been reported or proposed before. This compound is of great significance for the development and application of tumor treatment drugs. The proposal of the present invention will also provide a new drug and treatment plan for tumor treatment.

[0034] The above description is only an overview of the technical solution of this application. In order to be able to understand the technical means of this application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features, and advantages of this application more obvious and understandable, the following is a detailed description of the preferred embodiments of this application in conjunction with the drawings as follows.

[0035] Based on the following detailed description of the specific embodiments of this application in conjunction with the drawings, those skilled in the art will understand the above and other purposes, advantages, and features of this application more clearly. Description of the Drawings

[0036] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0037] Figure 1 Schematic structural diagram of a dodecaborane derivative labeled with an IR-780 fluorescent probe;

[0038] Figure 2 Schematic diagram of the synthesis reaction in which the IR-780 fluorescent probe structure and the dodecaborane structure are directly connected by a thioether bond;

[0039] Figure 3 Schematic diagram of the synthesis reaction when the IR-780 fluorescent probe structure and the dodecaborane structure are connected by a spacer;

[0040] Figure 4 Cell viability comparison of BSH-IR-780 for photothermal therapy on HepG2 cells;

[0041] Figure 5 Results of photothermal therapy of BSH-IR-780 on tumor-bearing mice. Detailed implementation manners

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. In the following description, specific details such as specific configurations and components are provided only to assist in a comprehensive understanding of the embodiments of the present application. Therefore, those skilled in the art should clearly understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Additionally, descriptions of known functions and structures are omitted in the embodiments for clarity and conciseness.

[0043] The term "and / or" in this article is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" in this article describes another association object relationship, indicating that two relationships can exist. For example, A / and B can represent: A exists alone, and A and B exist alone. Additionally, the character " / " in this article generally represents that the associated objects before and after are in an "or" relationship.

[0044] It should also be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion.

[0045] Example 1

[0046] This example introduces a dodecaborane derivative labeled with the IR-780 fluorescent probe.

[0047] This derivative includes an IR-780 fluorescent probe structure and a dodecaborane structure, and the synthetic structural formula is as shown in the appendix Figure 1 as follows, Figure 1 which is a schematic structural diagram of the dodecaborane derivative labeled with the IR-780 fluorescent probe. This derivative has the potential to be used as a drug compound for PTT, BNCT, and the combined treatment of PTT-BNCT.

[0048] In this derivative, the IR-780 fluorescent probe structure is derived from the residue after the reaction of the fluorescent probe molecule IR-780. Except for the elimination of a chlorine atom, other structures are retained and connected to other partial structures by eliminating the chlorine atom; the dodecaborane structure is derived from the residue after the reaction of mercaptododecaborate (BSH). The reaction occurs on the mercapto group connected to the dodecaborane and is connected to other structures by eliminating the H atom on the mercapto group.

[0049] This dodecaborane structure is derived from mercaptododecaborate (BSH). Mercaptododecaborane exists in the form of a divalent anion, and the corresponding cation is an alkali metal cation including lithium (Li + ), sodium (Na + ), potassium (K + ), rubidium (Rb + ), cesium (Cs + ) or quaternary ammonium salt (NH 4 + ) and their mixtures.

[0050] In this derivative, the IR-780 fluorescent probe structure and the dodecaborane structure in the molecule can be directly connected through the thioether bond in BSH, as shown in the appendix Figure 1 where n = 0; or they can be connected through a series of spacers with different lengths, as shown in the appendix Figure 1 where n ≥ 1.

[0051] Among them, as shown in the appendix Figure 1As shown in [the figure], when connected by a spacer group, the spacer group can be a saturated alkane structure composed of two methylene groups, i.e., n = 1 as marked in the structural formula; it can also be a polyether structure, i.e., n = 2, 3, 4, …, 20 and their mixtures in the structural formula, but n does not exceed 20 at most.

[0052] Furthermore, when the IR-780 fluorescent probe structure and the dodecaborane structure are connected by a spacer group, the reactants constituting the spacer group structure are the reaction residues of α, ω-haloalcohols, specifically including 2-haloethanol (n = 0), 2-(2-haloethoxy)ethanol (n = 1), 2-[2-(2-haloethoxy)ethoxy]ethanol (n = 2), 2-[2-[2-(2-haloethoxy)ethoxy]ethoxy]ethanol (n = 3), 2-[2-[2-[2-(2-haloethoxy)ethoxy]ethoxy]ethoxy]ethanol (n = 4), α-hydroxy-ω-halopolyethylene glycol (5 ≤ n ≤ 20) and their mixtures; the halogen therein includes fluorine (F), chlorine (Cl), bromine (Br) or iodine (I) and mixtures of different haloalcohols.

[0053] These compounds are all formed through the nucleophilic substitution reaction between the halogen group of the substituted alkyl and the mercapto group or the hydroxyl group. The halogen group can be either chlorine in the IR-780 fluorescent probe molecule or the halogen element in the haloalcohol, including fluorine (F), chlorine (Cl), bromine (Br) or iodine (I) and mixtures composed of these haloalcohols.

[0054] Furthermore, as Figure 2 shown, Figure 2 is the schematic diagram of the synthesis reaction in which the IR-780 fluorescent probe structure and the dodecaborane structure are directly connected by a thioether bond. When the IR-780 fluorescent probe structure and the dodecaborane structure are directly connected by the thioether bond in BSH, the synthesis reaction is completed in one step; the theoretical molar ratio between the two raw material reactants of the IR-780 fluorescent probe structure and the dodecaborane is 1:1, but in the actual reaction, IR-780 will be in relative excess, and the available excess ratio is 10 - 100%. The preferred excess ratio is 10 - 50%.

[0055] Furthermore, as Figure 3 shown, Figure 3 is the schematic diagram of the synthesis reaction when the IR-780 fluorescent probe structure and the dodecaborane structure are connected by a spacer group. When the IR-780 structure and the dodecaborane structure are connected by a spacer group, the synthesis reaction is completed in two steps.

[0056] Among them, the theoretical molar ratio between BSH and α,ω-haloalcohol in the first-step reaction is 1:1. However, in the actual reaction, α,ω-haloalcohol is in relative excess, and the available excess ratio is 10 - 1000%, preferably 100 - 500%. In the second-step reaction, the theoretical molar ratio between the intermediate product generated in the previous step and IR-780 is 1:1. However, in the actual reaction, IR-780 is in relative excess, and the available excess ratio is 10 - 100%, preferably 10 - 50%.

[0057] Among them, the nucleophilic substitution reactions in the synthesis process are all carried out in a suitable solvent system. The solvents in the nucleophilic substitution reaction include but are not limited to water, pentane, n-hexane, n-octane, n-heptane, cyclohexane, benzene, toluene, ethylbenzene, xylene, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, acetonitrile, ether, ethyl acetate, butyl acetate, tetrahydrofuran, ethylene glycol dimethyl ether, 1,4-dioxane, acetone, butanone, cyclohexanone, N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and their mixtures. Among them, water, dichloromethane, 1,2-dichloroethane, chloroform, acetonitrile, ether, tetrahydrofuran, acetone, N,N-dimethylformamide and dimethyl sulfoxide and their mixtures are preferred.

[0058] Among them, the nucleophilic substitution reactions in the synthesis process are all carried out in the presence of a base. The bases available in the nucleophilic substitution reaction include but are not limited to sodium hydroxide, potassium hydroxide, sodium methoxide, sodium ethoxide, triethylamine, triethylenediamine, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]-5-nonene (DBN), pyridine, 4-dimethylaminopyridine (DMAP), N-methylmorpholine, tetramethylethylenediamine, tetramethylguanidine (TMG) and their mixtures. The amount of the base added is usually equivalent to the reactant with a smaller molar equivalent in the reaction system but in appropriate excess, and the available excess ratio is 10 - 300%. The preferred excess ratio is 50 - 200%.

[0059] Among them, the synthesis reactions are all carried out at normal pressure between room temperature and the boiling point temperature of the solvent used. The specific temperature range is 0 - 190 °C, and the preferred temperature range is 20 - 100 °C.

[0060] Among them, the synthesis reactions are carried out under stirring, and the reaction time generally ranges from 0 to 96 hours depending on the temperature and specific varieties, and the preferred time is 8 to 48 hours.

[0061] Among them, the synthesis reactions are usually completed in an inert atmosphere such as nitrogen or argon atmosphere; or carried out in a vaporized solvent atmosphere obtained by first purging with an inert gas such as nitrogen or argon to remove oxygen and then maintaining the solvent reflux.

[0062] Furthermore, after the endpoint of the product is confirmed by thin-layer chromatography, it can be separated and purified by methods such as dialysis, column chromatography, or preparative liquid chromatography separation. The available mobile phases include, but are not limited to, water, methanol, ethanol, dichloromethane, 1,2-dichloroethane, chloroform, acetonitrile, ether, tetrahydrofuran, acetone, N,N-dimethylformamide, and dimethyl sulfoxide, as well as their mixtures; the final product is obtained as a solid after vacuum drying or freeze drying.

[0063] The IR-780 fluorescent probe-labeled dodecaborane derivative and its synthesis method have a clear reaction mechanism, a simple process, and are easy to implement. The BSH structure contains boron elements and each molecule has 12 boron atoms, which can be used as a boron carrier for BNCT treatment. When some or all of the boron atoms are 10 B isotopes, it will show better neutron capture efficiency.

[0064] Example 2

[0065] Based on the above Example 1, in this example, the IR-780 fluorescent probe-labeled dodecaborane derivative is specifically prepared.

[0066] Combined with Attached Figure 1 , Figure 1 is a schematic structural diagram of the IR-780 fluorescent probe-labeled dodecaborane derivative. Weigh 37.5 mg of IR-780 and 25 mg of CsBSH, dissolve them in 25 mL of dimethyl sulfoxide and transfer them to a flask. Dropwise add 30 μL of triethylamine under magnetic stirring, insert a nitrogen balloon to purge and remove oxygen, and stir the reaction at room temperature for 48 hours. After the reaction, dialyze the mixed solution in pure water for 24 hours, then centrifuge the liquid in the dialysis bag at 13000 rpm for 15 min, and take the supernatant to be freeze-dried to obtain the BSH-IR780 solid product, corresponding to the product with n = 0 in Attached Figure 1 .

[0067] Example 3

[0068] Based on Example 1, in this example, the IR-780 fluorescent probe-labeled dodecaborane derivative is prepared.

[0069] Combined with Attached Figure 1 , Figure 1Schematic diagram of the structure of the dodecaborane derivative labeled with the IR-780 fluorescent probe. Weigh 45 mg of IR-780 and dissolve it in 10 mL of chloroform. Dissolve 25 mg of CsBSH in 10 mL of pure water and add 1 mL of triethylamine. Transfer the two into a small glass bottle, showing a two-phase state with the aqueous phase on the upper layer. After purging with nitrogen to remove oxygen, seal the reaction bottle and stir vigorously at room temperature for 48 hours using magnetic stirring. Then stop stirring and let the reaction system separate into phases again. Take the aqueous phase and dialyze it in pure water for 24 hours. Then centrifuge the liquid in the dialysis bag at 13,000 rpm for 15 minutes and take the supernatant, which is freeze-dried to obtain the solid product of BSH-IR-780, corresponding to the product with Figure 1 n = 0 in the attachment.

[0070] Example 4

[0071] Based on Example 1, in this example, the dodecaborane derivative labeled with the IR-780 fluorescent probe was prepared.

[0072] Combined with the attachment Figure 1 , Figure 1 Schematic diagram of the structure of the dodecaborane derivative labeled with the IR-780 fluorescent probe. Weigh 25 mg of CsBSH and dissolve it in 10 mL of pure water. Add 15 mg of 2-[2-(2-chloroethoxy)ethoxy]ethanol and 50 μL of triethylamine. After purging with nitrogen, seal and stir the reaction for 24 hours. After confirming no residual CsBSH by thin-layer chromatography, elute and separate the reaction system with a 50% aqueous acetonitrile solution by column chromatography, and collect the intermediate product solution for standby. Additionally, dissolve 45 mg of IR-780 in DMSO, mix it with the above intermediate product solution, add 50 μL of triethylamine, purge with nitrogen, and then stir the reaction at 70 °C for 24 hours. The product is eluted and separated with a 50% aqueous acetonitrile solution by column chromatography and dried under vacuum to obtain the solid product, corresponding to the product with Figure 1 n = 2 in the attachment.

[0073] Example 5

[0074] Based on Example 1, in this example, the dodecaborane derivative labeled with the IR-780 fluorescent probe was prepared.

[0075] Combined with the attachment Figure 1 , Figure 1Schematic diagram of the structure of the dodecaborane derivative labeled with the IR-780 fluorescent probe. Weigh 25 mg of CsBSH and dissolve it in 10 mL of pure water. Add 25 mg of α,ω-chlorinated polyethylene glycol and 50 μL of triethylamine. After purging with nitrogen, seal and stir the reaction for 24 hours. After confirming no residual CsBSH by thin-layer chromatography, elute and separate the reaction system with a 50% aqueous acetonitrile solution by column chromatography, and collect the intermediate product solution for standby. Additionally, dissolve 45 mg of IR-780 in DMSO, mix it with the above intermediate product solution, add 50 μL of triethylamine, purge with nitrogen, and then stir the reaction at 70 °C for 48 hours. The product is eluted and separated with a 50% aqueous acetonitrile solution by column chromatography, and dried under vacuum to obtain a solid product, corresponding to the attached Figure 1 product which is a mixture with n≈7, 8, 9, 10, 11.

[0076] Example 6

[0077] Based on Example 4, but different from Example 4, 30 mg of 2-[2-[2-(2-bromoethoxy)ethoxy]ethoxy]ethanol was used, and the reaction time for the first step was 18 hours, with other conditions being the same, to obtain the corresponding attached Figure 1 product with n = 3.

[0078] Example 7

[0079] Based on Example 4, but different from Example 4, 12 mg of NaBSH was used, with other conditions being the same, to obtain the corresponding attached Figure 1 product with n = 2.

[0080] Example 8

[0081] Based on Example 5, but different from Example 5, 12 mg of 10 B-enriched Na 10 BSH was used, with other conditions being the same, to obtain the corresponding attached Figure 1 product with n = 2 but 10 B-enriched.

[0082] Example 9

[0083] This example demonstrates the comparison of cell viability of BSH-IR-780 in photothermal therapy on HepG2 cells through experiments.

[0084] HepG2 human liver cancer cells were seeded in a 24-well cell culture plate and incubated at 37 ± 0.5 °C with a CO2 concentration of 5%. After the cells reached a semi-confluent state, the BSH-IR-780 compound with n = 0 prepared in Example 2 was used as the drug for cell administration. During the administration process, DMSO was used as an organic adjuvant, and the concentration of DMSO was 0.5% - 5%, preferably 1% - 3%; the drug concentration was 5 - 200 μM, preferably 10 - 60 μM.

[0085] After administration, the cells were allowed to continue incubating at 37 ± 0.5 °C with a CO 2 concentration of 5% for 30 minutes; then the cells were washed repeatedly with PBS until all the unabsorbed drug was completely washed away. After that, the cells were irradiated with near-infrared light at a wavelength of 820 nm for simulated PTT treatment. The power of the near-infrared light was 1 W / cm2, and the irradiation time was 5 minutes. The cells after irradiation were cultured at 37 ± 0.5 °C with a CO 2 concentration of 5% for another 24 hours, and then the cell viability index was detected by the CCK-8 method to evaluate the treatment effect. As shown in the Figure 4 attachment, Figure 4 is the comparison of cell viability in the photothermal treatment of BSH-IR-780 on HepG2 cells. Figure 4 It is the treatment effect after cell PTT treatment with BSH-IR-780 as the drug based on the cell viability index.

[0086] Through experiments and Figure 4 the results showed that BSH-IR-780 at 10 - 30 μM combined with near-infrared light irradiation showed a positive treatment effect on HepG2 human liver cancer cells. Compared with the non-irradiation group, the tumor volume after treatment was significantly lower than that of the control group, indicating a clear potential as a drug candidate.

[0087] Example 10

[0088] In this example, photothermal treatment of BSH-IR-780 was carried out on tumor-bearing mice. As shown in the Figure 5 attachment, Figure 5 are the results of photothermal treatment of BSH-IR-780 on tumor-bearing mice.

[0089] The tumor-bearing mice were randomly divided into 3 groups, with 6 mice in each group. They were respectively injected with 0.9% NaCl normal saline and 0.2 mg / mL BSH-IR-780 prepared in Example 2 via the tail vein on the 0th day and the 7th day, and the dosage was 5 μL / g × mouse body weight (g). In one of the dosing groups, PTT treatment was performed 48 h after each dosing (the specific operation was to irradiate the tumor site with near-infrared light for 5 min after the mice were anesthetized by respiration); the other group did not receive PTT treatment, and the changes in the body weight and tumor volume of the mice were observed.

[0090] Figure 5 Shown is the change in the tumor volume of the three groups of mice during the 20-day observation period. It can be seen that the tumor volume of the mice that received the drug and PTT treatment was significantly smaller than that of the control group, indicating an obvious tumor treatment effect.

[0091] Example 11

[0092] In this example, 10 boron-enriched dodecaborane was used for synthesis to obtain 10 boron-enriched IR-780-labeled dodecaborane derivative, which became the boron carrier in BNCT treatment. Combining with the good effect demonstrated by PTT treatment in the foregoing examples, BNCT further killed tumor cells to obtain a better tumor treatment effect. The method that can be adopted is usually one BNCT treatment combined with multiple PTT treatments. PTT treatment is usually performed before BNCT treatment, or it can also be performed after BNCT treatment.

[0093] The above are only the preferred embodiments of the present application, and it does not limit the protection scope of the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any changes, modifications, substitutions, integrations, and parameter changes made to these embodiments by means of conventional substitutions or capable of achieving the same functions without departing from the principle and spirit of the present application fall within the protection scope of the present application.

Claims

1. An IR-780 fluorescent probe-labeled dodecaborane derivative, characterized in that, the derivative comprises an IR-780 fluorescent probe structure and a dodecaborane structure, and its anion structural formula is as follows: ； n is an integer from 0 to 20; the corresponding cation is Li+, Na+, K+, Rb+, Cs+ or NH4+ and their mixtures.

2. Preparation of an IR-780 fluorescent probe-labeled dodecaborane derivative according to claim 1, characterized in that, the IR-780 fluorescent probe structure in the derivative is from the residue after the fluorescent probe molecule IR-780 participates in the reaction. Except for eliminating one chlorine atom, other structures are retained and connected to other partial structures by eliminating the chlorine atom; the dodecaborane structure is from the residue after mercaptododecaborate BSH participates in the reaction. The reaction occurs on the mercapto group connected to the dodecaborane and is connected to other structures by eliminating the H atom on the mercapto group.

3. Preparation of an IR-780 fluorescent probe-labeled dodecaborane derivative according to claim 2, characterized in that, when the IR-780 fluorescent probe structure and the dodecaborane structure are connected by a spacer group, the reactant constituting the spacer group structure is the reaction residue of α,ω-haloalcohol.

4. Preparation of an IR-780 fluorescent probe-labeled dodecaborane derivative according to claim 2, characterized in that, when the IR-780 fluorescent probe structure and the dodecaborane structure are directly connected by a thioether bond, the synthesis reaction is completed in one step; after the reaction ends, the end point is confirmed by thin layer chromatography, and then separation and purification are carried out by dialysis, column chromatography or preparative liquid chromatography separation methods; the theoretical molar ratio between the two raw material reactants of the IR-780 fluorescent probe structure and the dodecaborane structure is 1:

1.

5. Preparation of an IR-780 fluorescent probe-labeled dodecaborane derivative according to claim 3, characterized in that, when the IR-780 fluorescent probe structure and the dodecaborane structure are connected by a spacer group, the synthesis reaction is completed in two steps: after the reaction ends, the end point is confirmed by thin layer chromatography, and then separation and purification are carried out by dialysis, column chromatography or preparative liquid chromatography separation methods; the theoretical molar ratio between BSH and α,ω-haloalcohol in the first step reaction is 1:

1. In the actual reaction, α,ω-haloalcohol is in relative excess, and the excess ratio used is 10 - 1000%; the theoretical molar ratio between the intermediate product generated in the previous step and IR-780 in the second step reaction is 1:

1. In the actual reaction, IR-780 is in relative excess, and the excess ratio used is 10 - 100%.

6. Preparation of an IR-780 fluorescent probe-labeled dodecaborane derivative according to claim 3, characterized in that, The solvents in the reaction are water, pentane, n-hexane, n-octane, n-heptane, cyclohexane, benzene, toluene, ethylbenzene, xylene, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, acetonitrile, diethyl ether, ethyl acetate, butyl acetate, tetrahydrofuran, ethylene glycol dimethyl ether, 1,4-dioxane, acetone, butanone, cyclohexanone, N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and their mixtures; The bases in the reaction are sodium hydroxide, potassium hydroxide, sodium methoxide, sodium ethoxide, triethylamine, triethylenediamine, 1,8-diazabicyclo[5.4.0]undec-7-ene DBU, 1,5-diazabicyclo[4.3.0]-5-nonene DBN, pyridine, 4-dimethylaminopyridine DMAP, N-methylmorpholine, tetramethylethylenediamine, tetramethylguanidine TMG and their mixtures.

7. Use of a dodecaborane derivative labeled with an IR-780 fluorescent probe according to claim 1 in the preparation of a medicament for tumor treatment.

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