Boron medicine with tumor targeted release capability for boron neutron capture therapy and preparation method thereof

Abstract

The invention provides a boron drug with tumor targeted release capability for boron neutron capture therapy and a preparation method thereof, relates to the technical field of tumor therapy, and provides a boron drug which can be activated through high-concentration NAD (P) H at a tumor site and can release a B-10 drug in a targeted manner for boron neutron capture therapy. A boron-10-containing compound in the boron medicine is connected with 3-aldehyde quinoline salt through a self-elimination reactive group, the 3-aldehyde quinoline salt can be specifically reduced by NAD (P) H rich in tumor cells to trigger chain reaction, and the effective boron-10 compound is released for boron neutron capture therapy. The damage to normal cells in the BNCT process can be effectively reduced by a method for targeted aggregation of the boron drug in the tumor cells. The boron drug synthesis method is simple, mild in condition and high in yield, has the advantages of stable chemical property, good light stability, small toxicity and the like, and provides a good application prospect for the field of boron neutron capture therapy.

Description

Technical Field

[0001] The present invention relates to the technical field of tumor treatment, and in particular to a boron medicine with tumor-targeted release capability for boron neutron capture treatment and a preparation method thereof. Background Art

[0002] Boron Neutron Capture Therapy (BNCT) is an advanced radiotherapy method for cancer. Its principle is that drugs carrying 10B are injected into the patient's body. The targeting of the drug causes 10B to selectively accumulate in tumor tissue. The affected area is irradiated with an epithermal neutron beam. The neutrons react with the 10B in the tumor cells to form the isotope 11B through a 10B(n,α)7Li nuclear reaction, which rapidly splits to produce 7Li and α particles. The DNA of cancer cells is irreversibly broken by the heavy ions and is precisely killed to achieve the purpose of treatment.

[0003] Ideal boron-containing drugs can reach high concentrations in tumor tissues and maintain this concentration during neutron irradiation, and have low toxicity. At present, borophenylalanine (BPA) and thiododecaborane disodium salt (BSH) are two commonly used boron carriers, but they both have major disadvantages. The disadvantages of BPA are low water solubility and potential toxic side effects, while the main disadvantage of BSH is that it cannot penetrate the blood-brain barrier and has low tumor uptake and retention capacity. These factors limit the effectiveness and popularity of these two boron carriers in clinical applications. The research on new targeted boron drugs has become a hot topic in BNCT research. At present, the research and development of boron drugs has undergone two generations of improvements. The goal of the third-generation boron drugs under development is to improve the high bioavailability, quantitative release, ability to cross the blood-brain barrier and ability to retain for a longer time of boron drugs.

[0004] Tumor-targeted boron drugs can be achieved by combining with tumor-targeting molecules, such as introducing certain specific antibodies, small molecule ligands, or being able to achieve targeted release at the tumor site. Compared with normal cells, tumor cells have high metabolic characteristics, and this characteristic is used by tumor cells to support their rapid proliferation. In the metabolism of tumor cells, the reduced form of nicotinamide adenine dinucleotide (NAD(P)H) plays an important role. NAD(P)H is an important molecule in cellular energy metabolism. It is produced during glycolysis and is used to produce ATP in the electron transport chain. Compared with normal cells, tumor cells usually show a stronger Warburg effect, which leads to a significant increase in the generation of cellular NAD(P)H. Therefore, it is necessary to construct NAD(P)H targeted release boron drugs to effectively increase the concentration of boron drugs at the tumor site and reduce the toxicity to normal cells during BNCT. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a novel boron drug with tumor-targeted release capability for boron neutron capture therapy. The method can improve the targeting and therapeutic effect of the boron drug and has good operability and repeatability.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for preparing a boron drug with tumor-targeted release capability for boron seed capture therapy, the synthesis route of the preparation method is as follows:

[0008]

[0009] Preferably, the preparation method comprises the following steps:

[0010] S1: dissolving quinoline-3-methanol in an organic solvent, adding a halogenating agent, reacting under reflux at 50-90° C. for 12-48 hours, cooling to room temperature and evaporating under reduced pressure to remove part of the organic solvent to obtain a crude product, and the crude product is recrystallized from anhydrous ether to obtain the product 3-(hydroxymethyl)-1-substituted quinoline salt;

[0011] S2: The intermediate product 3-(hydroxymethyl)-1-substituted quinoline salt and an appropriate amount of triphosgene are placed in a Schlenk bottle, and an ultra-dry organic solvent is added under anhydrous and oxygen-free conditions. Under an ice-water bath, nitrogen is bubbled for reaction for 20-60 minutes to obtain 1-substituted quinoline-3-chloroformic acid methyl ester, and 1-methylquinoline-3-chloroformic acid methyl ester solution is obtained.

[0012] S3: At 0°C, a 1-substituted quinolyl-3-chloroformic acid methyl ester solution is added to an ultra-dry N,N-dimethylformamide solution containing a boron-10 compound and diisopropylethylamine. After reacting for 2 hours, the solution is washed with saturated ammonium chloride to obtain the final boron drug product.

[0013] Preferably, the halogenating agent used in S1 is any one of chloro, bromo and iodo compounds.

[0014] Preferably, the reaction solvent used in S2 is any one of anhydrous acetonitrile, anhydrous tetrahydrofuran or anhydrous N,N-dimethylformamide.

[0015] Preferably, in the 3-(hydroxymethyl)-1-substituted quinolate in S1, the substituent group is any one of methyl, ethyl and hexanoic acid.

[0016] Preferably, the molar ratio of 3-(hydroxymethyl)-1-substituted quinoline salt to triphosgene in S2 is 1:1-1:20. A boron drug for boron seed capture therapy with tumor-targeted release capability is prepared using the above-mentioned preparation method.

[0017] Preferably, its molecular structure is as follows:

[0018]

[0019]

[0020] Preferably, the group in the compound that responds to NAD(P)H is a quinolyl salt substituted at position 3.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The boron drug prepared by the present invention can be activated by high-concentration NAD(P)H in the tumor site and targeted to release B-10 drug for boron neutron capture therapy, which has the advantages of strong targeting and high biosafety.

[0023] (2) The boron drug prepared by the present invention has tumor-targeted release for boron neutron capture therapy. The boron drug has a simple synthesis method, mild conditions, high yield, and has the advantages of stable chemical properties, good photostability and low toxicity, providing good application prospects in the field of boron neutron capture therapy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The ultraviolet absorption spectrum of a tumor-targeted boron drug prepared in Example 1 of the present invention at different NAD(P)H concentrations;

[0025] Figure 2 This is the fluorescence emission spectrum of a tumor-targeted boron drug prepared in Example 1 of the present invention at different NAD(P)H concentrations. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with specific embodiments.

[0027] The present application provides a method for preparing a boron drug with tumor-targeted release capability for boron seed capture therapy, and the synthesis route thereof is as follows:

[0028]

[0029] The preparation method comprises the following steps:

[0030] (1) Dissolve quinoline-3-methanol in an organic solvent, add a halogenating agent, reflux for reaction at 50-90° C. for 12-48 hours, cool to room temperature and remove part of the organic solvent under reduced pressure to obtain a crude product, and recrystallize the crude product from anhydrous ether to obtain the product 3-(hydroxymethyl)-1-substituted quinoline salt.

[0031] In the above step 1, the organic solvent used is acetonitrile or chloroform; the halogenation reagent is any one of chloro, bromo and iodo compounds. The 3-(hydroxymethyl)-1-substituted quinolate has a substituent group of any one of methyl, ethyl and hexanoic acid.

[0032] (2) The intermediate product 3-(hydroxymethyl)-1-substituted quinoline salt and an appropriate amount of triphosgene are placed in a Schlenk bottle, and an ultra-dry organic solvent is added under anhydrous and oxygen-free conditions. The reaction is stirred in an ice-water bath for 3 hours, and then nitrogen is introduced for 20 minutes to obtain a 1-methylquinoline-3-chloroformic acid methyl ester solution.

[0033] In the above step 2, the equivalent of 3-(hydroxymethyl)-1-substituted quinoline salt is 1 equivalent, the equivalent of triphosgene is 1-20 equivalents, and the organic solvent used in this step is anhydrous tetrahydrofuran or anhydrous N,N-dimethylformamide.

[0034] (3) At 0°C, a solution of 1-substituted quinolyl-3-chloroformic acid methyl ester was added to an ultra-dry N,N-dimethylformamide solution containing a boron-10 compound and diisopropylethylamine. After reacting for 2 hours, the reactant was neutralized with saturated ammonium chloride and extracted with dichloromethane. The collected organic portion was washed with brine, then dried over sodium sulfate, filtered and concentrated under reduced pressure to obtain a crude product. The crude product was purified by silica gel column chromatography to obtain a novel boron drug.

[0035] In the above step 3, the 1-substituted quinolate-3-chloroformic acid methyl ester is 1 equivalent, and the boron-10 compound is 1-10 equivalents.

[0036] Based on the above preparation method, the present application also provides a boron drug with tumor-targeted release for boron neutron capture therapy, the molecular structure of which is shown below:

[0037]

[0038] Based on the above-mentioned boron drug with tumor-targeted release for boron neutron capture therapy, the present application also provides the use of the above-mentioned boron drug in the preparation of tumor-targeted drugs.

[0039] The above contents are described below in conjunction with specific embodiments:

[0040] Synthesis of a boron drug with tumor-targeted release for boron neutron capture therapy

[0041]

[0042] (1) Weigh 2.0 g of quinoline-3-methanol into a 100 ml eggplant-shaped flask and add 30 ml of acetonitrile. After dissolving, add 5 ml of iodomethane, and the mixture is heated under reflux at 90°C for 12 hours. After the reaction is completed, cool to room temperature, remove most of the acetonitrile under reduced pressure distillation, and drop the product into anhydrous ether to precipitate a white solid. Filter with suction, add anhydrous ether to wash the filter cake three times, and obtain 3-(hydroxymethyl)-1-methylquinoline with a yield of 88%.

[0043] (2) Weigh 1 gram of 3-(hydroxymethyl)-1-methylquinoline and 15 grams of triphosgene in a 250 mL Schlenk bottle, evacuate for 1 minute, fill with nitrogen for 1 minute, and repeat this operation three times. Add 20 mL of anhydrous tetrahydrofuran to an ice-water bath, stir at room temperature for 3 hours, and then pass nitrogen for 20 minutes. After the reaction is completed, the intermediate product 1-methylquinoline-3-methyl chloroformate is obtained.

[0044] (3) 8 g of the boron-containing compound 10 and 3 mL of N,N-diisopropylethylamine were dissolved in 10 mL of anhydrous N,N-dimethylformamide, and then slowly added dropwise to a solution of 1-methylquinoline-3-chloroformic acid methyl ester in anhydrous tetrahydrofuran. After the reaction was carried out in an ice-water bath for 2 hours, the reactant was treated with saturated ammonium chloride and extracted with dichloromethane. The collected organic portion was washed with brine, then dried over sodium sulfate, filtered and concentrated under reduced pressure to obtain the final product with a yield of 84%.

[0045] Example 2 Synthesis of a boron drug with tumor-targeted release for boron neutron capture therapy

[0046]

[0047] (1) Weigh 2.0 g of quinoline-3-methanol into a 100 ml eggplant-shaped flask and add 30 ml of chloroform. After dissolving, add 5.0 g of 6-bromohexanoic acid, and the mixture is heated under reflux at 50°C for 48 hours. After the reaction is completed, cool to room temperature, remove chloroform under reduced pressure distillation, and drop the product into anhydrous ether to precipitate a white solid. Filter by suction, add anhydrous ether to wash the filter cake three times, and obtain 3-(hydroxymethyl)-1-carboxypentylquinoline with a yield of 80%.

[0048] (2) Weigh 1 gram of 3-(hydroxymethyl)-1-carboxypentylquinoline and 15 grams of triphosgene in a 250 mL Schlenk bottle, evacuate for 1 minute, fill with nitrogen for 1 minute, and repeat this operation three times. Add 20 mL of anhydrous N,N-dimethylformamide, and react by nitrogen bubbling for 30 minutes under ice-water bath conditions. After the reaction is completed, remove the excess triphosgene by nitrogen bubbling, and evacuate the solution to dryness to obtain the intermediate product 1-carboxypentylquinoline-3-methyl chloroformate.

[0049] (3) 8 g of the boron-10 compound and 3 mL of N,N-diisopropylethylamine were dissolved in 10 mL of anhydrous N,N-dimethylformamide, and then slowly added dropwise to a super-dry N,N-dimethylformamide solution of 1-carboxypentylquinoline-3-chloroformic acid methyl ester. After the reaction was carried out in an ice-water bath for 2 hours, the reactant was treated with saturated ammonium chloride and extracted with dichloromethane. The collected organic portion was washed with brine, then dried over sodium sulfate, filtered and concentrated under reduced pressure to obtain the final product with a yield of 70%.

[0050] Example 3 Test of the ability of the boron drug prepared in Example 1 to release boron-10 at different concentrations of NAD(P)H

[0051] (1) The boron drug release capacity tests were all completed in PIPES buffer (pH = 7.4).

[0052] (2) Prepare a 1.0 mM boron drug stock solution, add 10 μL of the stock solution to a quartz cuvette, dilute with PIPES buffer to a boron drug concentration of 20 μM, and then use a UV-visible spectrophotometer to measure the UV absorption spectra of different NAD(P)H concentrations in the range of 250-600 nm, such as Figure 1 shown.

[0053] (3) 10 μL of the boron drug stock solution prepared in step (1) was added to a cuvette, and the concentration was adjusted to 20 μM with PIPES buffer. Then, the fluorescence emission spectrum of the boron drug at different NAD(P)H concentrations in the range of 320-750 nm was tested using a fluorescence spectrometer. The excitation wavelength of the fluorescence spectrum was 390 nm, and the emission wavelength was 420 nm. Figure 2 shown.

[0054] In the present invention, the boron-10 compound in the new boron drug is connected to the 3-formaldehyde quinoline salt through a self-eliminating reaction group, and the 3-formaldehyde quinoline salt can be specifically reduced by NAD(P)H, which is abundant in tumor cells, to trigger a chain reaction, releasing an effective boron-10 compound for boron neutron capture therapy. This method of targeted aggregation of boron drugs in tumor cells can effectively reduce the damage to normal cells during BNCT. The present application verifies through specific examples that the boron drug prepared by the above preparation method can be activated by high-concentration NAD(P)H in the tumor site, and the B-10 drug is targeted for boron neutron capture therapy, which has the advantages of strong targeting and high biosafety. In addition, the synthesis method of the boron drug is simple, the conditions are mild, the yield is high, and it has the advantages of stable chemical properties, good photostability and low toxicity, providing a good application prospect in the field of boron neutron capture therapy.

Claims

1. A method for preparing a boron drug with tumor-targeted release capability for boron seed capture therapy, characterized in that: The synthetic route of the preparation method is as follows:

2. The method for preparing a boron drug with tumor-targeted release capability for boron seed capture therapy according to claim 1, characterized in that: The preparation method steps are as follows: S1: dissolving quinoline-3-methanol in an organic solvent, adding a halogenating agent, reacting under reflux at 50-90° C. for 12-48 hours, cooling to room temperature and removing part of the organic solvent by evaporation under reduced pressure to obtain a crude product, and adding the crude product dropwise into a large amount of anhydrous ether to precipitate, filtering the precipitate, and washing with ether to obtain the product 3-(hydroxymethyl)-1-substituted quinoline salt; S2: The intermediate product 3-(hydroxymethyl)-1-substituted quinoline salt and an appropriate amount of triphosgene are placed in a Schlenk bottle, and an ultra-dry organic solvent is added under anhydrous and oxygen-free conditions. The reaction is carried out in an ice-water bath with nitrogen bubbling for 20-60 minutes to obtain 1-substituted quinoline-3-chloroformic acid methyl ester, and a 1-methylquinoline-3-chloroformic acid methyl ester solution is obtained; S3: At 0°C, add the 1-substituted quinolyl-3-chloroformic acid methyl ester solution to an ultra-dry N,N-dimethylformamide solution containing a boron-10 compound and diisopropylethylamine. After reacting for 2 hours, wash with saturated ammonium chloride and extract with dichloromethane. The collected organic portion is washed with brine, then dried, filtered and concentrated under reduced pressure to obtain the final boron drug product.

3. The method for preparing a boron drug with tumor-targeted release capability for boron seed capture therapy according to claim 2, characterized in that: The halogenating agent used in S1 is any one of chloro, bromo and iodo compounds.

4. The method for preparing a boron drug with tumor-targeted release capability for boron seed capture therapy according to claim 2, characterized in that: The reaction solvent used in S2 is any one of anhydrous acetonitrile, anhydrous tetrahydrofuran or anhydrous N,N-dimethylformamide.

5. The method for preparing a boron drug with tumor-targeted release capability for boron seed capture therapy according to claim 4, characterized in that: In the 3-(hydroxymethyl)-1-substituted quinolate in S1, the substituent group is any one of methyl, ethyl and hexanoic acid.

6. The method for preparing a boron drug with tumor-targeted release capability for boron seed capture therapy according to claim 4, characterized in that: The molar ratio of 3-(hydroxymethyl)-1-substituted quinoline salt to triphosgene in S2 is 1:1-1:

20.

7. A boron drug for boron seed capture therapy with tumor-targeted release capability, characterized in that: The method is prepared by any one of claims 1 to 6.

8. The boron drug for boron seed capture therapy with tumor-targeted release capability according to claim 7, characterized in that: Its molecular structure is as follows:

9. The boron drug for boron seed capture therapy with tumor-targeted release capability according to claim 8, characterized in that: The group in the compound that responds to NAD(P)H is a quinolyl salt substituted at position 3.

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