Preparation method of biotin targeting molecular probe

Abstract

The invention discloses a biotin targeting molecular probe preparation method, which comprises: carrying out an amide condensation reaction on a compound 1 and a compound 2 in a solvent to obtain a compound 3; the chemical structural formula of the compound 1 is shown in the specification, wherein n is an integer of 0-4; the chemical structural formula of the compound 2 is shown in the specification, wherein a is an integer of 0-6. The use of non-environment-friendly solvents such as xylene is avoided, and the yield of the product can be improved.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology and relates to a method for preparing a molecular probe, specifically a method for preparing a biotin-targeting molecular probe. Background Technology

[0002] Biotin-alkyne (773888-45-2) is a biolabeling and molecular coupling tool product manufactured through organic synthesis. It combines the specific affinity of biotin with the click chemistry activity of the alkynyl group. Biotin can bind to streptavidin or avidin with high affinity and high specificity, with a dissociation constant as low as 10. -15 The concentration is at the mol / L level; alkyne groups can rapidly form stable covalent bonds with azide groups through copper-catalyzed or copper-free click reactions.

[0003] Chinese invention patent application number 201180052776.2 discloses a method for synthesizing biotin derivatives, which involves reacting biotin methyl ester with Lawson's reagent in an organic solvent such as xylene, using, for example, hydrogen peroxide or m-chloroperoxybenzoic acid (mCPBA) to oxidize the cyclic sulfur atoms in biotin derivative 67 to sulfones to prepare biotin derivative 68; the yield has room for improvement. Summary of the Invention

[0004] In view of this, the purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a biotin-targeting molecular probe.

[0005] To achieve the above objectives, the technical solution adopted by this invention is: a method for preparing a biotin-targeting molecular probe, comprising the following steps:

[0006] Compound 1 and compound 2 were subjected to an amide condensation reaction in a solvent to obtain compound 3;

[0007] The chemical structural formula of compound 1 is as follows: In the formula, n is an integer from 0 to 4;

[0008] The chemical structural formula of compound 2 is as follows: In the formula, a is an integer from 0 to 6;

[0009] The chemical structural formula of compound 3 is as follows:

[0010] Ideally, the molar ratio of compound 1 to compound 2 is 1.05 to 1.2:1.

[0011] Preferably, the solvent is a mixture of one or more selected from DMF, cyclohexane, chloroform, and ethyl acetate.

[0012] Ideally, the reaction temperature for the amide condensation is 40–60°C and the reaction time is 10–15 h.

[0013] Optimally, a condensing agent and an acylation catalyst are also added to the solvent, wherein the condensing agent is dicyclohexylcarbodiimide, the acylation catalyst is 4-pyrrolidinylpyridine, the amount of the condensing agent is 1.5 to 2.5 times the amount of 1 mole of the compound, and the amount of the acylation catalyst is 0.1 to 0.2 times the amount of 1 mole of the compound.

[0014] Ideally, after the amide condensation reaction is complete, the reaction product is cooled to -5 to 0°C and filtered to obtain the filtrate.

[0015] Further, the mother liquor is concentrated after filtration to obtain a crude product, which is then slurried with methanol and dried.

[0016] Due to the application of the above technical solutions, the present invention has the following advantages compared with the prior art: The preparation method of the biotin-targeted molecular probe of the present invention avoids the use of environmentally unfriendly solvents such as xylene by carrying out an amide condensation reaction of compound 1 and compound 2 in a solvent, thereby improving the yield of the product. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the preparation process of the biotin-targeting molecular probe of the present invention.

[0018] Figure 2 This is the NMR spectrum of the biotin-targeting molecular probe of this invention. Detailed Implementation

[0019] The method for preparing the biotin-targeting molecular probe of the present invention, such as... Figure 1 As shown, the process includes the following steps: reacting compound 1 and compound 2 in a solvent via an amide condensation reaction to obtain compound 3; the chemical structural formula of compound 1 is: In the formula, n is an integer from 0 to 4; the chemical structural formula of compound 2 is: In the formula, a is an integer from 0 to 6; the chemical structural formula of compound 3 is as follows: By carrying out an amide condensation reaction between compound 1 and compound 2 in a solvent, the use of environmentally unfriendly solvents such as xylene is avoided, and the yield of the product can be improved.

[0020] The molar ratio of compound 1 to compound 2 is 1.05–1.2:1. The solvent is a mixture selected from one or more of DMF, cyclohexane, chloroform, and ethyl acetate. The amide condensation reaction temperature is 40–60°C, and the reaction time is 10–15 h. A condensation reagent and an acylation catalyst are also added to the solvent. The condensation reagent is dicyclohexylcarbodiimide, and the acylation catalyst is 4-pyrrolidinylpyridine. The amount of the condensation reagent is 1.5–2.5 times the molar amount of compound 1, and the amount of the acylation catalyst is 0.1–0.2 times the molar amount of compound 1. After the amide condensation reaction is completed, the reaction product is cooled to -5–0°C and filtered to obtain a filtrate. The mother liquor is concentrated after filtration to obtain a crude product, which is then slurried with methanol and dried. All the above steps can improve the product yield.

[0021] The preferred embodiments of the present invention will now be described in detail.

[0022] Example 1

[0023] This embodiment provides a method for preparing a biotin-targeting molecular probe, the chemical structural formula of which is as follows: Includes the following steps:

[0024] Compound 1 (110 mmol, 26.88 g) and compound 2 Add 100 mmol, 5.5 g of DMF (400 ml) and react at 40 °C overnight (10 h);

[0025] After the amide condensation reaction was completed, the reaction product was cooled to 0°C and filtered to obtain the filtrate. After filtration, the mother liquor was concentrated by vacuum distillation to obtain the crude product. 100 ml of methanol was added and stirred, allowed to stand, filtered, and the stirring was repeated 2 to 3 times. The product was then dried at 40 to 60°C to obtain 25.8 g of product (yield 91.8%).

[0026] Example 2

[0027] This embodiment provides a method for preparing a biotin-targeted molecular probe, which is basically the same as that in Example 1, except that: 30.95 g (150 mmol) of dicyclohexylcarbodiimide and 1.48 g (10 mmol) of 4-pyrrolidinylpyridine are added to the solvent for reaction; 27.2 g of product is obtained (yield 96.5%). Figure 2 (As shown).

[0028] Comparative Example 1

[0029] This example provides a method for preparing a biotin-targeted molecular probe, which is basically the same as that in Example 1, except that the product is filtered at room temperature to obtain 22.5g of the final product (yield 79.8%).

[0030] Comparative Example 2

[0031] This example provides a method for preparing a biotin-targeted molecular probe, which is basically the same as that in Example 1, except that: 30.95 g (150 mmol) of dicyclohexylcarbodiimide and 1.22 g (10 mmol) of 4-N,N-dimethylpyridine are added to the solvent for reaction; 17.4 g of product is obtained (yield 62.1%).

[0032] Comparative Example 3

[0033] This example provides a method for preparing a biotin-targeted molecular probe, which is basically the same as that in Example 1, except that: 18.93 g (150 mmol) of diisopropylcarbodiimide and 1.48 g (10 mmol) of 4-pyrrolidinylpyridine are added to the solvent for reaction; 24.0 g of product is obtained (yield 85.2%).

[0034] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a biotin-targeting molecular probe, characterized in that, Includes the following steps: Compound 1 and compound 2 were subjected to an amide condensation reaction in a solvent to obtain compound 3; The chemical structural formula of compound 1 is as follows: In the formula, n is an integer from 0 to 4; The chemical structural formula of compound 2 is as follows: In the formula, a is an integer from 0 to 6; The chemical structural formula of compound 3 is as follows:

2. The method for preparing the biotin-targeting molecular probe according to claim 1, characterized in that: The molar ratio of compound 1 to compound 2 is 1.05 to 1.2:

1.

3. The method for preparing the biotin-targeting molecular probe according to claim 1, characterized in that: The solvent is a mixture of one or more selected from DMF, cyclohexane, chloroform, and ethyl acetate.

4. The method for preparing the biotin-targeting molecular probe according to claim 1, characterized in that: The reaction temperature for the amide condensation is 40–60°C, and the reaction time is 10–15 h.

5. The method for preparing the biotin-targeting molecular probe according to claim 1, characterized in that: A condensing agent and an acylation catalyst are also added to the solvent. The condensing agent is dicyclohexylcarbodiimide, and the acylation catalyst is 4-pyrrolidinylpyridine. The amount of the condensing agent is 1.5 to 2.5 times the amount of 1 mole of the compound, and the amount of the acylation catalyst is 0.1 to 0.2 times the amount of 1 mole of the compound.

6. The method for preparing the biotin-targeting molecular probe according to claim 1, characterized in that: After the amide condensation reaction is completed, the reaction product is cooled to -5 to 0°C and filtered to obtain the filtrate.

7. The method for preparing the biotin-targeting molecular probe according to claim 6, characterized in that: After filtration, concentrate the mother liquor to obtain the crude product, add methanol to make a slurry, and then dry it.

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