Preparation method of high-purity somatotropin

Abstract

The application belongs to the technical field of compound synthesis, and particularly relates to a preparation method of high-purity boswellin. The preparation method of the high-purity boswellin comprises the following steps: (1) reacting D-xylose, acetylacetone and an alkaline substance in an alcohol solvent, and then adsorbing and purifying to obtain an intermediate compound; (2) reacting the intermediate compound, a reducing agent and a catalyst, and then adsorbing and purifying to obtain a target boswellin; the alkaline substance is sodium phosphate and / or potassium phosphate; the reducing agent is isopropanol; and the catalyst is alkoxyaluminum or samarium iodide. The preparation method is characterized by mild process conditions, high reaction efficiency and low cost, and experiments prove that the boswellin prepared by the method is a high-purity boswellin product without boron (not detected) and salt (electrical conductivity is less than or equal to 20), and the liquid chromatography purity reaches 99.9%, which is very suitable for industrialized preparation and application of boswellin.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of compound synthesis, and particularly relates to a preparation method of high-purity Pro-Xylane. BACKGROUND

[0002] Pro-Xylane (hydroxypropyl tetrahydropyran triol) is a xylose derivative with anti-aging activity, which can promote the synthesis of collagen, make the skin more tough and elastic, and improve the fine lines on the neck and prevent aging, and has important application value in the field of cosmetics and skin care products.

[0003] The specific structure of Pro-Xylane (hydroxypropyl tetrahydropyran triol) is as follows:

[0004]

[0005] The Pro-Xylane on the market is mainly divided into three types according to the chiral ratio of the 7th carbon, which are liquid paste with S:R of 50:50, liquid paste with S:R of 70:30, and white solid powder with S:R ratio greater than 99:1.

[0006] In the prior art, the main synthesis method of Pro-Xylane is to react D-xylose (raw material 1) with acetylacetone under the action of alkali to generate intermediate 2, and then to reduce sodium borohydride to obtain Pro-Xylane (compound 3), and the specific technical route is as follows:

[0007]

[0008] The main defect of the above process is that when producing intermediate 2, it is difficult to extract intermediate 2 from water, which makes it difficult to recover and purify intermediate 2, and increases the operation difficulty. In addition, in the production of Pro-Xylane, the reducing agent used is sodium borohydride, which is difficult to separate from the product, and compound 3 is also difficult to separate from water, resulting in that the salt content and boron content of the obtained Pro-Xylane (compound 3) are both high, far exceeding the specifications of the cosmetic industry, which limits its further application.

[0009] Therefore, how to develop a new preparation method of Pro-Xylane to prepare high-purity Pro-Xylane without salt and boron has become a technical problem to be solved by the present application. SUMMARY

[0010] To solve the above problems existing in the prior art, the first purpose of the present application is to provide a preparation method of high-purity Pro-Xylane, which is simple in process and can prepare high-purity Pro-Xylane without salt and boron.

[0011] In order to achieve the above purpose, the technical scheme adopted by the present application is:

[0012] A preparation method of high-purity boswellin, comprising the following steps:

[0013] (1) reacting D-xylose, acetylacetone and an alkaline substance in an alcohol solvent, and then performing adsorption purification to obtain an intermediate compound;

[0014] (2) reacting the intermediate compound, a reducing agent and a catalyst, and then performing adsorption purification to obtain the target boswellin;

[0015] The intermediate compound has the structural formula The alkaline substance is sodium phosphate and / or potassium phosphate; the reducing agent is isopropanol; and the catalyst is alkoxyaluminum or samarium iodide.

[0016] The preparation method of high-purity boswellin provided by the application uses an alcohol solvent as a reaction medium when synthesizing the intermediate compound in step (1), so that the use of water can be avoided, and special alkaline substances (sodium phosphate and potassium phosphate) are used, which will not generate water through neutralization reaction, so that the introduction of water into the reaction system is further avoided. After the reaction is completed, the reaction system does not contain water, so that the product is easy to separate, a large amount of inorganic salt can be removed through a simple adsorption purification process, and the intermediate compound is obtained. Further, in step (2) for synthesizing the target boswellin, the intermediate compound is used as a carbonyl compound to be reacted, alkoxyaluminum or samarium iodide is used as a catalyst, and isopropanol is used as a reducing agent to perform Meerwein-Ponndorf-Verley reduction reaction to prepare boswellin, and finally, a simple adsorption purification process is combined to remove trace inorganic salt.

[0017] The preparation method of the application has the advantages of mild process conditions, high reaction efficiency, low cost, and the like. Test results show that, through comprehensive improvement of the alkaline substance, the reaction solvent, the reduction process and the purification process, the prepared boswellin is a high-purity boswellin product without boron (not detected), without salt (electrical conductivity ≤ 20), and with a liquid chromatography purity of 99.9%, which is very suitable for industrialized preparation and application of boswellin.

[0018] As a preferred scheme, in step (1), the alcohol solvent is selected from one or any combination of methanol, ethanol and isopropanol. The alcohol solvent used in the application can ensure effective dissolution of the reaction raw materials D-xylose and acetylacetone and improve the reaction efficiency, so that the use of water is effectively avoided, and the problem that the intermediate compound is difficult to purify in water is solved.

[0019] Based on the consideration of improving the reaction efficiency and reducing the cost of raw materials, as a preferred scheme, in step (1), the molar ratio of D-xylose, acetylacetone and the alkaline substance is 1:2:2; and the dosage ratio of D-xylose to the alcohol solvent is 1g:(4-6)mL.

[0020] As a preferred scheme, in step (1), the reaction is a heating reflux reaction; the temperature of the heating reflux reaction is 80-90℃, and the time is 1-2h.

[0021] As a preferred scheme, in step (2), the usage ratio of the intermediate compound, the reducing agent and the catalyst is 1g:(4-6)mL:(0.106-2.14)g.

[0022] As a preferred scheme, the aluminum alkoxide is triisopropyl aluminum.

[0023] As a preferred scheme, in step (2), when the target is a liquid-state boson, the reaction is a heating reflux reaction, the temperature is 70-90℃, and the time is 1-2h; when the target is a solid-state boson, the reaction is a conventional heating reaction, the temperature is 45-55℃, and the time is 20-30h. The conventional heating reaction is a conventional heating reaction without reflux.

[0024] Further preferably, in step (2), when the target is a solid-state boson, an acidic substance is further added in the reaction system; the acidic substance is one or any combination of acetic acid, propionic acid and trifluoroacetic acid. In the synthesis of boson in step (2), the reaction rate and the reaction degree can be adjusted by whether the acidic substance is added or not on the basis of the catalyst and the reducing agent, so that high-purity, boron-free, salt-free colorless transparent liquid or white solid powder (the state of the product obtained is different according to the ratio of SR) with different chiral proportions is obtained, which can better meet the diversified demand of boson products in different forms in the market.

[0025] As a preferred scheme, in steps (1) and (2), activated carbon and silica gel are used as the adsorption materials.

[0026] Further preferably, in step (1), the mass ratio of activated carbon to silica gel is 1:(8-12); in step (2), the mass ratio of activated carbon to silica gel is 1:(2.1-2.2). BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 HNMR spectrum of the intermediate compound obtained in step (1) in the preparation method of the high-purity boson of Example 1 of the present application;

[0028] Figure 2 Liquid chromatogram of the intermediate compound obtained in step (1) in the preparation method of the high-purity boson of Example 1 of the present application;

[0029] Figure 3The HNMR spectrum of the target object, the somatotropin, obtained in step (2) in the preparation method of the high-purity somatotropin of the present application;

[0030] Figure 4 The liquid chromatogram of the target object, the somatotropin, obtained in step (2) in the preparation method of the high-purity somatotropin of the present application. DETAILED DESCRIPTION

[0031] The technical solutions and technical effects of the present application are further explained below in combination with specific embodiments and drawings. The following description is only used to explain the present application and should not be understood as a limitation on the protection scope of the present application. In the following examples, the methods used are all conventional methods in the art unless otherwise specified. In the following examples, the reagents used are all conventional reagents in the art unless otherwise specified and can be obtained from commercial channels.

[0032] The preparation method of the high-purity somatotropin provided below in the present application comprises the following steps:

[0033] (1) reacting D-xylose, acetylacetone and an alkaline substance in an alcohol solvent, and then adsorbing and purifying to obtain an intermediate compound;

[0034] (2) reacting the intermediate compound, a reducing agent and a catalyst, and then adsorbing and purifying to obtain the target object, the somatotropin;

[0035] The structure of the intermediate compound is The alkaline substance is sodium phosphate and / or potassium phosphate; the reducing agent is isopropanol; and the catalyst is alkoxyaluminum or samarium iodide.

[0036] Preferably, in step (1), the alcohol solvent is selected from one or any combination of methanol, ethanol and isopropanol.

[0037] In step (1), the molar ratio of D-xylose, acetylacetone and the alkaline substance is 1:2:2; and the use amount ratio of D-xylose to the alcohol solvent is 1g:(4-6)mL.

[0038] In step (1), the reaction is a heating reflux reaction; the heating reflux reaction temperature is 80-90℃ and the time is 1-2h.

[0039] Preferably, in step (2), the mass ratio of the intermediate compound to the catalyst is 1:(0.106-2.14); more preferably, when the catalyst is alkoxyaluminum, the mass ratio of the intermediate compound to the catalyst is 1:2.14; and when the catalyst is samarium iodide, the mass ratio of the intermediate compound to the catalyst is 1:0.106. The use amount ratio of the intermediate compound to the reducing agent is 1g:(4-6)mL.

[0040] Preferably, the aluminum alkoxide is aluminum isopropoxide.

[0041] As a preferred solution, in step (2), when the target is liquid boswellic acids, the reaction is a heating reflux reaction, the temperature is 70-90°C, and the time is 1-2 hours; when the target is solid boswellic acids, the reaction is a conventional heating reaction, the temperature is 45-55°C, and the time is 20-30 hours. The conventional heating reaction is a conventional heating reaction without reflux.

[0042] In step (1) and step (2), the adsorption purification uses activated carbon and silica gel as adsorption materials.

[0043] Further preferably, in step (1), the mass ratio of activated carbon to silica gel is 1: (8-12), and more preferably 1:10. In step (2), the mass ratio of activated carbon to silica gel is 1: (2.1-2.2). The mesh number of silica gel is 300-400 mesh. Further preferably, in step (1), the mass ratio of D-xylose to activated carbon is 10:1. In step (2), the mass ratio of the intermediate compound to activated carbon is 10:1.

[0044] Example 1

[0045] The preparation method of high-purity boswellic acids in this embodiment is for liquid boswellic acids, and the specific steps are as follows:

[0046] (1) Put D-xylose (100 g), ethanol (500 mL), and acetylacetone (133 g) into a three-necked flask, then add potassium phosphate (282 g), wherein the molar ratio of D-xylose, acetylacetone, and potassium phosphate is 1:2:2. After adding, heat to 80-90°C, reflux for 1-2 hours, and detect the end of the reaction by HPLC. Cool and filter, wash the solid with ethanol, then combine the washing liquid and the filtrate, dilute in the combined liquid with ethyl acetate (1 L), then add 10 g of activated carbon and 100 g of silica gel, stir at room temperature for 30 min for adsorption purification. Then filter, concentrate, and finally beat with ethyl acetate to obtain 88.6 g of an intermediate compound in the form of a white solid, with the structural formula of The yield is 70%, and the liquid chromatography (HPLC) purity is 99.991%.

[0047] The structure characterization of the intermediate compound is shown in the HNMR spectrum as Figure 1 The characterization data are as follows: 1H NMR (400 MHz, Deuterium Oxide): δ 3.89 (dd, J = 11.3, 5.4 Hz, 1H), 3.71 (td, J = 9.6, 2.8 Hz, 1H), 3.57 (td, J = 9.9, 5.3 Hz, 1H), 3.40 (t, J = 9.1 Hz, 1H), 3.27 (t, J = 11.0 Hz, 1H), 3.20 (t, J = 9.3 Hz, 1H), 3.03 (dd, J = 17.0, 2.8 Hz, 1H), 2.69 (dd, J = 17.0, 9.4 Hz, 1H), 2.24 (s, 3H).

[0048] The liquid chromatogram of the intermediate compound is shown in Figure 2 Figure 2 The HPLC purity of the intermediate compound is shown to reach 99.991%.

[0049] (2) Intermediate 2 (100 g), isopropyl alcohol (500 mL), samarium iodide (10.6 g) were added to a three-necked flask, and after addition, heated to 80-90°C, refluxed for 1-2 hours, and HPLC detection was performed to determine the end of the reaction. After the reaction was completed, it was cooled to room temperature, then diluted with ethyl acetate (1 L), and then 10 g of activated carbon and 21 g of silica gel were added, stirred at room temperature for 30 min for adsorption purification, then filtered and concentrated to obtain 97.8 g of colorless oily liquid, which was the target substance, boselide.

[0050] The structure characterization HNMR spectrum of the target substance boselide of Example 1 is shown in Figure 3 1 H NMR (400 MHz, Deuterium Oxide): δ 4.01 (dt, J = 8.2, 4.0 Hz, 1H), 3.92 (dt, J = 11.4, 5.8 Hz, 1H), 3.56 (td, J = 10.0, 5.4 Hz, 1H), 3.47-3.20 (m, 3H), 3.15 (q, J = 8.7 Hz, 1H), 1.91 (dd, J = 14.5, 8.4 Hz, 1H), 1.64 (ddd, J = 14.8, 9.6, 5.9 Hz, 0.5H), 1.56-1.43 (m, 0.5H), 1.19 (dd, J = 6.2, 4.5 Hz, 3H).

[0051] The liquid chromatogram of the intermediate compound is shown in Figure 4 Figure 4 The HPLC purity of the target substance boselide is shown to reach 99.991%.

[0052] Example 2

[0053] ​​​The preparation method of the high-purity boswelia in the embodiment is to prepare liquid boswelia, and the specific steps are as follows:

[0054] (1) D-xylose (100 g), methanol (400 mL), acetylacetone (133 g) are added into a three-necked flask, and then potassium phosphate (282 g) is added, wherein the molar ratio of D-xylose, acetylacetone and potassium phosphate is 1:2:2. After adding, heating to 70-80 DEG C, refluxing for 1-2 hours, and detecting the reaction end by HPLC. Cooling and filtering, washing the solid with ethanol, then combining the washing liquid and the filtrate, diluting the combined liquid with ethyl acetate (1 L), then adding 10 g of activated carbon and 100 g of silica gel, stirring for 30 min at room temperature for adsorption purification. Then filtering, concentrating, and finally slushing with ethyl acetate to obtain 85 g of intermediate compound in the form of white solid, and the structural formula is The yield is 67.1%, and the purity of liquid chromatography (HPLC) is 99.99%. The structural characterization results of the intermediate compound of example 2 are the same as those of example 1, which will not be repeated here.

[0055] (2) Intermediate 2 (100 g), isopropyl alcohol (500 mL), triisopropoxy aluminum (214 g) are added into a three-necked flask, and then heated to 80-90 DEG C, refluxing for 1-2 hours, and detecting the reaction end by HPLC. After the reaction is completed, cool to room temperature, then dilute with ethyl acetate (1 L), and then add 10 g of activated carbon and 21.4 g of silica gel, stir for 30 min at room temperature for adsorption purification, then filter, concentrate, and obtain 93.7 g of colorless oily liquid, which is the target boswelia.

[0056] The structural characterization results of the target boswelia of example 2 are basically similar to those of example 1, and the difference between them is only the different chiral proportion of the carbon at 7 position.

[0057] Example 3

[0058] The preparation method of the high-purity boswelia in the embodiment is to prepare liquid boswelia, and the specific steps are as follows:

[0059] (1) D-xylose (100 g), isopropyl alcohol (600 mL), acetylacetone (133 g) are added into a three-necked flask, and then sodium phosphate (220 g) is added, wherein the molar ratio of D-xylose, acetylacetone and sodium phosphate is 1:2:2. After adding, heating to 80-90 DEG C, refluxing for 1-2 hours, and detecting the reaction end by HPLC. Cooling and filtering, washing the solid with ethanol, then combining the washing liquid and the filtrate, diluting the combined liquid with ethyl acetate (1 L), then adding 10 g of activated carbon and 100 g of silica gel, stirring for 30 min at room temperature for adsorption purification. Then filtering, concentrating, and finally slushing with ethyl acetate to obtain 95 g of intermediate compound in the form of white solid, and the structural formula is Yield 72.6%, liquid chromatography (HPLC) purity 99.99%. The structural characterization results of the intermediate compound of Example 3 are the same as those of Example 1, which are not described here again.

[0060] (2) Intermediate 2 (100 g), isopropyl alcohol (500 mL), samarium iodide (10.6 g), trifluoroacetic acid (60 g) were added into a three-necked flask, and after addition, heated to 50°C for conventional reaction for 24 h, and HPLC detection was used to determine the end of the reaction. After the reaction was completed, it was cooled to room temperature, then diluted with ethyl acetate (1 L), and then 10 g of activated carbon and 21 g of silica gel were added, stirred at room temperature for 30 min for adsorption purification, then filtered and concentrated to obtain 60 g of white solid, which was the target product, bosentan.

[0061] The structural characterization results of the target product bosentan of Example 3 are basically similar to those of Example 1, and the only difference between them is the different chiral ratio of the carbon at position 7.

[0062] Test Example

[0063] The yield, HPLC purity, boron content, S:R ratio, water content, and conductivity (10% aqueous solution) of the target product bosentan prepared in Examples 1-3 were tested. Among them, the purity test used high performance liquid chromatography; the boron content test used derivatization method; the S:R ratio was determined by evaporative light detector; the water content test used Karl Fischer method; and the conductivity test used 10% bosentan aqueous solution directly for instrument determination. The results are shown in Table 1.

[0064] Table 1: Index determination results of bosentan prepared in Examples 1-3

[0065]

[0066] As can be seen from Table 1, using the preparation method of the present application, high-purity (LC 99.9% or more), boron-free (not detected), salt-free (conductivity ≤20) high-quality bosentan products can be prepared, and by changing the test parameters, bosentan products with different S / R ratios and different product states of liquid or solid can be conveniently prepared, greatly meeting the industrialized preparation needs of bosentan products with different forms, and having important value for promoting the application of bosentan in cosmetics and skin care products.

Claims

1. A method for preparing high purity somatotropin, characterized by, The method comprises the following steps: (1) reacting D-xylose, acetylacetone and an alkaline substance in an alcohol solvent, and then adsorbing and purifying to obtain an intermediate compound; (2) reacting the intermediate compound, a reducing agent and a catalyst, and then adsorbing and purifying to obtain the target Bose factor; The structural formula of the intermediate compound is as follows: The alkaline substance is sodium phosphate and / or potassium phosphate; the reducing agent is isopropanol; the catalyst is samarium iodide; in steps (1) and (2), activated carbon and silica gel are used as adsorption materials for the adsorption purification.

2. The method for preparing high-purity Bosein according to claim 1, characterized in that, In step (1), the alcohol solvent is selected from one or any combination of methanol, ethanol and isopropanol.

3. The method for preparing high-purity Bosein according to claim 1, characterized in that, In step (1), the molar ratio of D-xylose, acetylacetone and the alkaline substance is 1:2:2; the ratio of the amount of D-xylose to the alcohol solvent is 1g:(4-6)mL.

4. The method for preparing high-purity Bosein according to claim 1, characterized in that, In step (1), the reaction is a heating reflux reaction; the heating reflux reaction is performed at a temperature of 80-90°C for 1-2h.

5. The method for preparing high-purity Bosein according to any one of claims 1 to 4, characterized in that, In step (2), the ratio of the amount of the intermediate compound, the reducing agent and the catalyst is 1g:(4-6)mL:(0.106-2.14)g.

6. The method of claim 1 to 4, wherein the high purity somatotropin is prepared by the steps of: In step (2), when the target product is a liquid Bose factor, the reaction is a heating reflux reaction, which is performed at a temperature of 70-90°C for 1-2h; when the target product is a solid Bose factor, the reaction is a conventional heating reaction, which is performed at a temperature of 45-55°C for 20-30h.

7. The method for preparing high-purity Bosein according to claim 6, characterized in that, In step (2), when the target product is a solid Bose factor, an acidic substance is further added to the reaction system; the acidic substance is one or any combination of acetic acid, propionic acid and trifluoroacetic acid.

8. The method for preparing high-purity Bosein according to claim 1, characterized in that, In step (1), the mass ratio of activated carbon to silica gel is 1:(8-12) during adsorption and purification; in step (2), the mass ratio of activated carbon to silica gel is 1:(2.1-2.2) during adsorption and purification.

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