A preparation method of pharmaceutical grade sodium dibutyryl adenosine cyclophosphate

Abstract

The present invention relates to a preparation method of pharmaceutical grade sodium dibutyryl adenosine cyclophosphate, comprising the steps of salt formation, acylation, refining, drying and the like. In the acylation process, a gradient program temperature rise method is adopted to accurately control the progress of the reaction, the reaction conversion rate is high, the side reaction is less, the impurity content of the finished product is extremely low, and a high-purity sodium dibutyryl adenosine cyclophosphate product is obtained. In the refining step, different solvents are used for multiple stirring and washing, and the organic solvents and impurities remaining in the purification and synthesis process of sodium dibutyryl adenosine cyclophosphate are effectively removed by centrifugation, thereby improving the purity of the product. The purity of the sodium dibutyryl adenosine cyclophosphate product prepared by the present invention can reach more than 99.5%. The preparation method of the present invention has simple process, mild reaction conditions, easy operation, stable process, good reproducibility, high total yield, and is more suitable for industrial production.

Description

Technical Field

[0001] The invention relates to the technical field of drug synthesis, and in particular to a method for preparing pharmaceutical-grade sodium dibutyryl adenosine cyclophosphate. Background Art

[0002] Sodium dibutyryladenosine cyclophosphate is a drug first applied for listing in Japan by Daiichi Sankyo Company Limited in 1984. There is no report of the drug being marketed in China. Sodium dibutyryladenosine cyclophosphate for injection can treat postoperative shock and severe heart failure, and the sodium salt in the form of an ointment is mainly used to treat skin diseases such as bedsores. The original research route developed by the company uses cycloadenosine as the starting material, which is reacted with butyric anhydride after being salified with triethylamine to obtain crude dibutyryladenosine cyclophosphate, and then sodium dibutyryladenosine cyclophosphate is obtained through cation exchange resin. The ion exchange resin used in this process has low exchange capacity, low yield and high cost; the post-reaction treatment is complicated, and cation exchange resin is used, which is not conducive to industrial production. At the same time, the impurity problem has not been well solved.

[0003] There are few reports in China on the synthesis method of sodium dibutyryladenosine cyclophosphate, which are mainly about the synthesis method of calcium dibutyryladenosine cyclophosphate, that is, based on the synthesis process of sodium dibutyryladenosine cyclophosphate, the sodium used for salt formation is replaced by calcium chloride to obtain calcium dibutyryladenosine cyclophosphate. However, the chemical purity of the product obtained by the process operation reported in the current literature cannot meet the requirements for pharmaceutical use; although there are also literature reports that the final product with a purity of 99.0% can be obtained by separation and purification technologies such as spray drying and column chromatography, this type of purification process is complicated to operate, labor-intensive, has high requirements on equipment, and is costly, and cannot meet the requirements of enterprise production.

[0004] Therefore, it is of great practical significance to find a production process for sodium dibutyryladenosine cyclophosphate with lower production cost, less impurities and higher chemical purity. Summary of the invention

[0005] In order to overcome the problem of poor purity of sodium dibutyryl adenosine cyclophosphate products in the prior art, the present invention provides a method for preparing sodium dibutyryl adenosine cyclophosphate. The purity of sodium dibutyryl adenosine cyclophosphate obtained by the method is ≥99.5%. In order to achieve the above-mentioned invention purpose, the present invention provides the following technical scheme: The present invention provides a method for preparing crude sodium dibutyryl adenosine cyclophosphate, comprising the following steps: (1) at room temperature, the raw material adenosine cyclophosphate is added into an aqueous sodium hydroxide solution. After the addition is completed, anhydrous ethanol is slowly added within 1 to 4 hours, and stirred for 1 to 2 hours, and the filter cake is collected by centrifugation; the filter cake is fully mixed with methyl tert-butyl ether in a ratio of 1:1 to 3, stirred and washed for 1 to 2 hours, and the filter cake is obtained by centrifugation; the filter cake is dried to a moisture content of ≤2.0%, and the drying is stopped to obtain crude sodium dibutyryl adenosine cyclophosphate; (2) the crude sodium dibutyryl adenosine cyclophosphate, butyric anhydride and triethylamine are mixed in a mass ratio of 1:(1 to 3):(0 .5~2) are fully mixed, the reaction temperature is: 70~140℃, and the temperature is increased by gradient heating; after the reaction is completed, the reaction solution is concentrated under reduced pressure until it becomes viscous, the temperature is lowered to below 100℃, and 1,4-dioxane is slowly added at 70~100℃; the mixture is stirred for 0.5~3h at this temperature, and the wet product is obtained by centrifugation; the wet product is dried to a moisture content of ≤15.0% to obtain a crude dibutyryl adenosine sodium cyclophosphate product; (3) the dried crude dibutyryl adenosine sodium cyclophosphate product is refined to obtain a fine dibutyryl adenosine sodium cyclophosphate product; (4) the fine dibutyryl adenosine sodium cyclophosphate product is dried at 20~50℃ to a moisture content of less than 4.0%, and after drying, a finished dibutyryl adenosine sodium cyclophosphate product is obtained.

[0006] Furthermore, in step (1), the mass ratio of cyclic adenosine monophosphate to sodium hydroxide aqueous solution is 1:1-3; the mass fraction of sodium hydroxide aqueous solution is 60%-95%; and the amount of anhydrous ethanol added is 1-7.5 times the weight of cyclic adenosine monophosphate.

[0007] Furthermore, in step (2), the temperature is increased by a gradient heating method, specifically: the reaction temperature in the three stages of the gradient heating is: 70°C to 90°C for 1 to 2 hours, 100 to 120°C for 2 to 3 hours, and 130 to 140°C for 1 to 2 hours.

[0008] Furthermore, the refining in step (3) is specifically as follows: ① putting the crude dibutyryl sodium adenosine cyclophosphate into an elution solvent, stirring and washing it for 2 to 5 times at 20 to 40° C., each time for 0.5 to 2 hours; and obtaining a wet product after centrifugation; wherein the elution solvent is: one or more selected from methyl tert-butyl ether, 1,4-dioxane, acetone, ethanol, ether, and isopropanol; and the mass ratio of the crude dibutyryl sodium adenosine cyclophosphate to the elution solvent is 1:1 to 5.

[0009] ② Dissolve the wet product in a mixed solvent consisting of acetone and water, stir at 15±5°C until the solution is clear; then add 0.1-10% of the weight of the wet product in activated carbon, stir and wash for 0.5-2 hours, filter, add 1-25 parts by weight of acetone relative to the wet product to the filtrate, stir at 15±5°C for 1-4 hours; centrifuge to obtain the fine product of dibutyryladenosine sodium cyclophosphate. The mass ratio of water to acetone in the mixed solvent is 1:1-10.

[0010] Beneficial Effects

[0011] (1) In the preparation method of sodium dibutyryl adenosine cyclophosphate provided by the present invention, a method of different gradient programmed temperature rise is adopted, which can effectively control the progress of the reaction, has a high reaction conversion rate, few side reactions, and easy control of impurities in the finished product, thereby ensuring the quality requirements of sodium dibutyryl adenosine cyclophosphate.

[0012] (2) In the preparation method of sodium dibutyryl adenosine cyclophosphate provided by the present invention, different solvents are used for stirring and washing in batches, and the organic solvents and impurities remaining in the purification and synthesis process of sodium dibutyryl adenosine cyclophosphate are removed to the maximum extent during the centrifugation process, which helps to improve the purity of the refined product.

[0013] (3) The preparation method of sodium dibutyryladenosine cyclophosphate of the present invention is simple, has mild reaction conditions, short reaction time, saves energy, produces less impurities, and has high product purity after washing; at the same time, the solvent used in this process can be recycled and reused at low temperature, reducing environmental pressure and being suitable for industrial production and promotion.

[0014] The present invention discloses a method for preparing sodium dibutyryl adenosine cyclophosphate, and those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0015] Add 40 kg of 80% sodium hydroxide to the reactor, then add 40 kg of cyclophosphate solid in batches and stir until dissolved. Stir and slowly add 200 kg of anhydrous ethanol, and control the addition time to 2 hours. After stirring for 1 hour, centrifuge and collect the filter cake.

[0016] Add 100 kg of methyl tert-butyl ether to the reactor, start stirring, add the filter cake obtained by centrifugation to the reactor, stir at 20-30° C. for 1 hour, and centrifuge to collect filter cake 2. Spread filter cake 2 on a plate, dry at 30-40° C. for 2 hours, then heat to 100° C., dry until the moisture content is ≤2.0%, stop drying, and discharge to obtain crude sodium cyclic adenosine monophosphate for later use.

[0017] 50g of sodium cyclophosphate adenosine prepared in Example 1, 80g of butyric anhydride and 30g of triethylamine were put into the reaction bottle and stirred. The temperature was raised to (reaction 1 was heated to 80℃ for 1h, 100℃ for 2h, 130℃ for 1h; reaction 2 was 80℃; reaction 3 was 100℃; reaction 4 was 120℃; reaction 5 was 130℃; reaction 6 was 140℃) for 4h, and after completion, the temperature was lowered to below 100℃, 140g of 1,4-dioxane was added for dilution, stirred for 1h, and filtered under reduced pressure to obtain a crude product, which was vacuum dried at 60℃.

[0018]

[0019] Through reaction observation, the reaction at 80-100℃ is relatively mild, but the reaction time is relatively long and there are more impurities; the reaction at 120-140℃ for 2h is basically complete, and no raw materials are detected, indicating that the reaction speed is very fast, but the reaction liquid is black, and the post-processing is difficult. In addition, the brown solid obtained by crystallization during the post-processing process has serious hygroscopicity, and it takes multiple crystallizations to obtain a solid without obvious hygroscopicity. The yield is significantly worse than the reaction effect of the gradient heating method of reaction 1. However, when the reaction temperature is raised to 120℃~140℃, the related substance N6-butyryl impurity in the crude product is not detected, and the size of the remaining impurities changes little with the increase of reaction time.

[0020] Reaction 1 adopts the temperature gradient method to heat up the synthesis, and the reaction process is uniform and controllable, which reduces the cumbersome post-reaction treatment caused by the violent reaction, and the reaction yield is significantly better than the reaction yield under other reaction temperature conditions.

[0021] Add 60 kg of butyric anhydride to the reactor, add 38 kg of crude sodium adenosine cyclophosphate (prepared in Example 1) and 25 kg of triethylamine under stirring, heat to 80 ° C for 1 hour, 100 ° C for 2 hours, and 130 ° C for 1 hour to carry out acylation reaction until the solid is dissolved. After the acylation reaction is completed, keep the reaction solution boiling and reduce pressure to concentrate until the reaction solution is viscous. After completion. Cool to below 100 ° C, slowly add about 380 kg of 1,4-dioxane, after addition, cool the reaction solution to 20-30 ° C, stir for about 1 hour, and centrifuge to obtain a wet product. Dry the wet product to a moisture content of ≤15.0% to obtain a crude sodium dibutyryl adenosine cyclophosphate.

[0022] Reaction a: ① Add 50 kg of methyl tert-butyl ether to the reactor, start stirring, and add 10 kg of crude dibutyryl adenosine cyclophosphate sodium to the reactor. Stir at 20-30°C for 1 hour, and centrifuge to obtain a wet product. Repeat the above operation twice to obtain a wet product.

[0023] ② Add 15 kg of 1,4-dioxane to the reactor, start stirring, then add the wet product obtained in step ①, and stir until dissolved. Then slowly add 1,4-dioxane (about 25 kg) at 30±5℃, continue to keep warm and stir for 2 hours, and centrifuge to obtain the wet product. Repeat the above operation once more to obtain the wet product.

[0024] ③ Add 15 kg of acetone to the reaction kettle, start stirring, then add the wet product prepared in step ②, keep warm and stir at 25±5℃ for 1 hour, and centrifuge to obtain the wet product. Add 50 kg of acetone to the reaction kettle, start stirring, then add the above wet product, keep warm and stir at 25±5℃ for 1 hour, and centrifuge to obtain the wet product.

[0025] ④ Add 40kg acetone to the decolorization kettle, start stirring, then add the wet product obtained in step ③ and 6kg purified water, keep warm and stir at 15±5℃ until dissolved. Then add 0.1kg activated carbon, stir at 15±5℃ for 0.5h, filter the liquid and transfer it to the crystallization kettle. Slowly add 200kg acetone to the crystallization kettle, keep warm at 15±5℃ and stir for 1h, and centrifuge to obtain the wet product.

[0026] ⑤ Place the wet product obtained in step ④ in a dryer and dry at 20-50° C. until the water content is less than 4.0%, and obtain the fine product of sodium dibutyryl cyclophosphate.

[0027] Reaction b: ① Add 20 kg of methyl tert-butyl ether to the reactor, start stirring, and add 10 kg of crude dibutyryl adenosine cyclophosphate sodium to the reactor. Stir for 2 hours at 30-40 ° C, and centrifuge to obtain a wet product. Add 20 kg of methyl tert-butyl ether to the reactor, start stirring, and add the above wet product to the reactor. Stir for 2 hours at 30-40 ° C, and centrifuge to obtain a wet product.

[0028] ② Add 20 kg of ethanol to the reactor, start stirring, and add the wet product prepared in step ① to the reactor. Start stirring, stir at 30-40°C for 1 hour, and centrifuge to obtain a wet product. Add 10 kg of ethanol to the reactor, start stirring for 0.5 hour, add the above wet product to the reactor, stir at 30-40°C for 2 hours, discharge and centrifuge to obtain a wet product.

[0029] ③ Add 30 kg of 1,4-dioxane to the reaction kettle, start stirring, then add the wet product prepared in step ②, and stir until dissolved. Then slowly add 1,4-dioxane (about 10 kg) at 25±5℃, continue to keep warm and stir for 1.5 hours, and centrifuge to obtain wet product 1.

[0030] ④ Add 20 kg of acetone to the reaction kettle, start stirring, keep the wet product prepared in step ③ warm and stir at 35±5℃ for 2 hours, and centrifuge to obtain a wet product. Add 50 kg of acetone to the reaction kettle, start stirring, then add the above wet product, keep warm and stir at 25±5℃ for 1 hour, and centrifuge to obtain a wet product.

[0031] ⑤ Add 40kg acetone to the decolorization kettle, start stirring, then add the wet product prepared in step ④ and 10kg purified water, keep warm and stir at 15±5℃ until dissolved. Then add 0.1kg activated carbon, stir at 15±5℃ for 1.0h, filter and transfer to the crystallization kettle. Slowly add 150kg acetone to the crystallization tank, keep warm at 15±5℃ and stir for 3h, and centrifuge to obtain the wet product.

[0032] ⑥Put the wet product obtained in step ⑤ in a dryer and dry it at 20-50° C. until the water content is less than 4.0%, and the product is a fine product of sodium dibutyryl adenosine cyclophosphate.

[0033] Reaction c: ① Add 30 kg of methyl tert-butyl ether to the reactor, start stirring, and add 10 kg of crude dibutyryl adenosine cyclophosphate sodium to the reactor. Stir at 20-30°C for 2 hours, discharge the material and centrifuge to obtain a wet product. Repeat the above operation 3 times to obtain a wet product.

[0034] ② Add 30 kg of acetone to the reaction kettle, start stirring, then add the wet product prepared in step ①, keep warm and stir at 25±5℃ for 1.5 hours, discharge and centrifuge to obtain a wet product. Add 50 kg of acetone to the reaction kettle, start stirring, then add the above wet product, keep warm and stir at 25±5℃ for 1.5 hours, discharge and centrifuge to obtain a wet product.

[0035] ③ Add 30kg acetone to the decolorization kettle, start stirring, then add the wet product prepared in step ② and 10kg purified water, keep warm and stir at 15±5℃ until dissolved. Then add 0.1kg activated carbon, stir at 15±5℃ for 1.5h, filter and transfer to the crystallization kettle. Slowly add 150kg acetone to the crystallization tank, keep warm at 15±5℃ and stir for 1h, discharge and centrifuge to obtain the wet product.

[0036] ④Put the wet product obtained in step ③ in a dryer and dry it at 20-50°C until the water content is less than 4.0%, and obtain the fine product of sodium dibutyryl adenosine cyclophosphate.

[0037] The dibutyryladenosine sodium cyclophosphate prepared in reactions a, b, and c were tested for related substances and residual solvents. The results are shown in Table 2 below.

[0038]

[0039] As can be seen from Table 2, the purity of the refined sodium dibutyryladenosine cyclophosphate product refined by the method is above 99.5%, and the maximum single impurity is less than 0.3%; the method of the present invention can effectively remove the impurities contained in the crude sodium dibutyryladenosine cyclophosphate, and can stably control the impurity content to obtain a high-purity product; at the same time, the residual solvent can be effectively controlled within the national standard range, and the obtained sodium dibutyryladenosine cyclophosphate product can meet the requirements of injection production.

Claims

1. A method for preparing pharmaceutical grade sodium dibutyryladenosine cyclophosphate, characterized in that The following steps are involved: (1) Under room temperature, the raw material adenosine cyclophosphate is added into a sodium hydroxide aqueous solution. After the addition is completed, anhydrous ethanol is slowly added within 1 to 4 hours, and stirred for 1 to 2 hours, and the filter cake is collected by centrifugation; the filter cake is fully mixed with methyl tert-butyl ether at a weight ratio of 1:1 to 3, stirred and washed for 1 to 2 hours, and the filter cake is centrifuged to obtain a filter cake; the filter cake is dried until the moisture content is ≤2.0%, and the drying is stopped to obtain a crude product of sodium cyclophosphate; (2) The crude sodium cyclophosphate adenosine, butyric anhydride and triethylamine are fully mixed in a mass ratio of 1: (1-3): (0.5-2), the reaction temperature is 70-140°C, and the temperature is increased by a gradient heating method; after the reaction is completed, the reaction solution is concentrated under reduced pressure until it becomes viscous, the temperature is lowered to below 100°C, and 1,4-dioxane is slowly added at 70-100°C; the mixture is stirred for 0.5-3h, and a wet product is obtained by centrifugation; the wet product is dried to a moisture content of ≤15.0%, and a crude sodium dibutyryl cyclophosphate adenosine is obtained; the temperature is increased by a gradient heating method, specifically: the reaction temperature in the three stages of the gradient heating is: 70-90°C for 1-2h, 100-120°C for 2-3h, and 130-140°C for 1-2h; (3) refining the dried crude dibutyryl adenosine sodium cyclophosphate to obtain a refined dibutyryl adenosine sodium cyclophosphate; (4) Drying the dibutyryl adenosine sodium cyclophosphate product at 20-50° C. until the water content is less than 4.0%. After drying, the dibutyryl adenosine sodium cyclophosphate product is obtained.

2. The method for preparing pharmaceutical grade sodium dibutyryladenosine cyclophosphate according to claim 1, characterized in that: In the step (1), the mass ratio of cyclic adenosine monophosphate to sodium hydroxide aqueous solution is 1:1-3; the mass fraction of the sodium hydroxide aqueous solution is 60%-95%; and the amount of anhydrous ethanol added is 1-7.5 times the weight of cyclic adenosine monophosphate.

3. The method for preparing pharmaceutical grade sodium dibutyryladenosine cyclophosphate according to claim 1, characterized in that: The refining in step (3) is specifically as follows: ①Put the crude product of dibutyryladenosine sodium cyclophosphate into the elution solvent, stir and wash it 2 to 5 times at 20 to 40°C, each time for 0.5 to 2 hours; centrifuge to obtain the wet product; ② Dissolve the wet product in a mixed solvent consisting of acetone and water, and stir at 15±5°C until it becomes clear; then add 0.1-10% of the weight of the wet product in activated carbon, stir and wash for 0.5-2 hours, filter, add 1-25 parts by weight of acetone relative to the wet product to the filtrate, stir at 15±5°C for 1-4 hours; centrifuge to obtain the fine product of dibutyryl adenosine sodium cyclophosphate.

4. The method for preparing pharmaceutical grade sodium dibutyryladenosine cyclophosphate according to claim 3, characterized in that: In the step ①, the elution solvent is selected from one or more of methyl tert-butyl ether, 1,4-dioxane, acetone, ethanol, ether, and isopropanol; and the mass ratio of the added crude sodium dibutyryladenosine cyclophosphate to the elution solvent is 1:1 to 5.

5. The method for preparing pharmaceutical grade sodium dibutyryladenosine cyclophosphate according to claim 3, characterized in that: In the step ②, the mass ratio of water to acetone in the mixed solvent is 1:1-10.

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