A method for preparing cefoperazone core and its application

Abstract

This invention discloses a method for preparing cefbiromate core and its application, relating to the field of compound preparation technology. The method for preparing the cefbiromate core includes the following steps: reacting 7-ACA with an active ester under alkaline conditions; after enzymatic hydrolysis and carboxyl protection, the reactants are obtained as the cefbiromate core. This method is environmentally friendly, has high production efficiency, and yields cefbiromate cores with high purity and good yield. It avoids the need for reprocessing due to the presence of certain impurities, thus improving production efficiency. The obtained cefbiromate core is suitable for preparing cefbiromate.

Description

Technical Field

[0001] This invention relates to the field of compound preparation technology, and in particular to a method for preparing cefoperazone nucleus and its application. Background Technology

[0002] Cefbiro ester is a prodrug of cefbiro. Once in the human body, it is rapidly hydrolyzed by non-specific esterifying enzymes to the active form of cefbiro, a new generation of broad-spectrum intravenous cephalosporin with activity against methicillin-resistant Staphylococcus aureus and Gram-negative bacteria (including some Pseudomonas aeruginosa). Cefbiro ester is obtained from the cefbiro ester nucleus through oxidation, Wittig reaction, deprotection, and esterification. Currently, the synthesis process of the cefbiro ester nucleus uses D-7ACA (Formula 1) as the starting material, reacting it with the active ester (Formula 2) under alkaline conditions, followed by protection of the carboxylic acid group to obtain the cefbiro ester nucleus (Formula 3). The specific reaction process is as follows:

[0003] .

[0004] However, in the current synthesis process, the starting material D-7ACA (3-deacetyl-7-aminocephalosporanic acid) has poor solubility, requires the strong base tetramethylguanidine for catalysis when reacting with the active ester, and contains many impurities, easily generating impurities as shown in Formula 12. Meanwhile, the 7-ADCA impurity in commercially available D-7ACA feedstock negatively impacts the quality of the cefoperazone core. Furthermore, in the current synthetic route, because the 3-position of the starting material D-7ACA is an exposed hydroxyl group, most of the active ester reacts simultaneously at both the 3 and 7 positions of D-7ACA during reaction with the active ester, generating impurities as shown in Formula 13. This affects product quality and leads to a lower yield. Summary of the Invention

[0005] The present invention aims to at least solve one of the aforementioned technical problems existing in the prior art. Therefore, the objective of the present invention is to provide a method for preparing cefbiloprost nucleus, using 7-ACA as the starting material, reacting it with an active ester followed by enzymatic hydrolysis and carboxyl protection to obtain the cefbiloprost nucleus, resulting in a product with high purity and yield.

[0006] A second aspect of the present invention is to provide a method for preparing cefoperazone.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] The first aspect of the present invention provides a method for preparing cefoperazone nucleus, comprising the following steps:

[0009] 7-ACA was reacted with the active ester under alkaline conditions. After enzymatic hydrolysis and carboxyl protection, the cefoperazone nucleus was obtained.

[0010] The cefoperazone core has the structure shown in Formula 3:

[0011] ;

[0012] In this context, R1 is a hydroxyl protecting group and R2 is a carboxyl protecting group.

[0013] This invention employs a novel synthetic route to prepare cefbiloreprin cores. Using stable 7-ACA as the starting material, the 7-amino group is first acylated by reaction with an active ester, followed by enzymatic removal of the 3-acetyl group. After carboxyl protection, the cefbiloreprin core is obtained. This method is environmentally friendly, highly efficient, and yields cefbiloreprin cores with high purity and good yield, avoiding the drawbacks of Formula 12. Or Equation 13 The presence of certain impurities indicates that rework is required, reducing production efficiency.

[0014] In some embodiments, the active ester has the structure shown in Formula 2: Wherein, R1 is a hydroxyl protecting group, and Y is an active group selected from the following Y1~Y3:

[0015] Where * represents the linking site with -CO in Formula 2, for example, when Y is Y1, the structure of the active ester is... .

[0016] Specifically, the hydroxyl protecting group can be triphenylmethyl; the carboxyl protecting group comes from a carboxyl protecting agent, such as diphenyldiazomethane.

[0017] In some embodiments, R1 is selected from alkyl, cycloalkyl, aralkyl, or triphenylmethyl; R2 is selected from diphenylmethyl, tert-butyl, p-nitrobenzyl, p-methoxybenzyl, or methoxymethyl.

[0018] In some embodiments, the enzyme used in the enzymatic hydrolysis process is a deacetylesterase.

[0019] In some embodiments, arginine and potassium phosphate are also added during the enzymatic hydrolysis process.

[0020] In the preparation of the cefoperazone core of the present invention, enzymatic hydrolysis is performed on the reactant obtained by the reaction of 7-ACA with the active ester, which has the structure shown in Formula 5. The compound has a sterically hindered group at position 7, resulting in low efficiency for enzymatic hydrolysis due to enzyme binding difficulties. Furthermore, the enzyme's activity is low in organic solvents, further reducing hydrolysis efficiency. While stepwise methods can improve efficiency to some extent—for example, dissolving the intermediate in pure aqueous solution to overcome activity loss in organic solvents—this approach complicates the synthetic route and introduces impurities during sample transfer. This invention addresses this by adding arginine and potassium phosphate to regulate the enzyme's conformation and charge balance, making it easier for the enzyme to bind to the substrate. This improves the deacetylesterase's binding ability to the compound of formula 5 and reduces the enzyme's inactivation rate in organic solvents. Hydrolysis can then be performed in a mixture of organic solvent and water, eliminating the need for stepwise preparation and resulting in higher reaction and production efficiency.

[0021] In some embodiments, the enzyme used for enzymatic hydrolysis is a deacetylesterase, and arginine and potassium phosphate are added during the enzymatic hydrolysis process.

[0022] In some embodiments, the mass ratio of the deacetylesterase, arginine, and potassium phosphate is (1-6):1:1. For example, the mass ratio of the deacetylesterase, arginine, and potassium phosphate can be 1:1:1, 1.5:1:1, 2:1:1, 3:1:1, 4:1:1, 5:1:1, or 6:1:1.

[0023] In some preferred embodiments, the mass ratio of the deacetylesterase, arginine, and potassium phosphate is (1~3):1:1.

[0024] In some embodiments, the mass ratio of the enzyme used in the enzymatic hydrolysis to the 7-ACA is (0.5~2):1. Specifically, the mass ratio of the enzyme used in the enzymatic hydrolysis to the 7-ACA can be 0.5:1, 0.8:1, 1:1, 1.2:1, 1.5:1, or 2:1.

[0025] In some preferred embodiments, the mass ratio of the enzyme used for enzymatic hydrolysis to the 7-ACA is (0.5~1.5):1.

[0026] In some other preferred embodiments, the mass ratio of the enzyme used for enzymatic hydrolysis to the 7-ACA is (0.8~1.2):1.

[0027] In some embodiments, the pH of the enzymatic hydrolysis is 6-9. For example, the pH of the enzymatic hydrolysis is 6, 7, 8, 8.2, 8.5, or 9. Enzymes are easily inactivated at pH values ​​above 10. By controlling the pH, the activity of the enzyme can be maintained and the hydrolysis efficiency can be improved, which helps to further increase the yield of the product.

[0028] In some preferred embodiments, the pH of the enzymatic hydrolysis is 8-9.

[0029] In some other preferred embodiments, the pH of the enzymatic hydrolysis is 8.3 to 8.6.

[0030] In some embodiments, the enzymatic hydrolysis temperature is 10-30°C. In other embodiments, the enzymatic hydrolysis temperature is 10-25°C. At temperatures below 10°C, enzyme activity decreases significantly, making the reaction difficult. This invention, by controlling the enzymatic hydrolysis temperature, can further ensure enzyme activity, improve hydrolysis efficiency, and increase product yield and purity.

[0031] In some preferred embodiments, the enzymatic hydrolysis temperature is 10~20℃.

[0032] In some other preferred embodiments, the enzymatic hydrolysis temperature is 15~20°C.

[0033] In some preferred embodiments, the enzymatic hydrolysis includes the following steps:

[0034] The product obtained by reacting 7-ACA with the active ester is cooled, the pH is adjusted to 6-9, the temperature is raised to 10-30℃, deacetylesterase, arginine and potassium phosphate are added, the pH is adjusted to 6-9, and enzymatic hydrolysis is carried out; after enzymatic hydrolysis, the deacetylesterase is removed by filtration.

[0035] In some embodiments, the reaction of the 7-ACA with the active ester satisfies at least one of the following reaction conditions:

[0036] a) The reaction temperature is -10~25℃;

[0037] b) The reaction solvent includes at least one of N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide.

[0038] In some preferred embodiments, the reaction temperature of the 7-ACA with the active ester is 0~20°C. For example, the reaction temperature is 0°C, 5°C, 10°C, 15°C, or 10°C.

[0039] In some other preferred embodiments, the reaction temperature of the 7-ACA with the active ester is 0~15°C.

[0040] In some embodiments, the alkaline conditions are provided by an alkaline solvent, which includes at least one of trimethylamine, triethylamine, dimethylethylamine, methyldiethylamine, tripropylamine, and tributylamine.

[0041] In some preferred embodiments, the reaction of the 7-ACA with the active ester includes the following steps:

[0042] 7-ACA was dissolved in the reaction solvent, and an alkaline solvent was added to provide alkaline conditions, followed by the addition of the active ester to carry out the reaction.

[0043] In some preferred embodiments, after the 7-ACA reacts with the active ester, a washing step is further included: the solution obtained after the reaction is diluted with water, and the aqueous layer is washed with ethyl acetate.

[0044] In some embodiments, the carboxyl protection includes the following steps: mixing the product obtained from the enzymatic hydrolysis with an organic solvent and a carboxyl protecting agent, reacting, and completing the carboxyl protection.

[0045] In some preferred embodiments, the carboxyl protection includes the following steps: mixing the product obtained from the enzymatic hydrolysis with an organic solvent and a carboxyl protecting agent, adjusting the pH to 2.5-3.5, reacting, and completing the carboxyl protection.

[0046] In some preferred embodiments, the organic solvent comprises dichloromethane; the carboxyl protecting agent comprises diphenyldiazonium methane. Specifically, the diphenyldiazonium methane is a dichloromethane solution of diphenyldiazonium methane, wherein the content of diphenyldiazonium methane in the solution is 0.3~0.8 mol / L.

[0047] In some preferred embodiments, the reaction is carried out at 0-5°C for 1-3 hours.

[0048] In some preferred embodiments, after carboxyl protection, a purification step is further included: the product after carboxyl protection is completed is separated into layers, the organic layer is washed and concentrated, stirred and pulped, and then filtered, washed and dried to obtain the cefoperazone nucleus.

[0049] Specifically, the organic layer can be washed with cold brine, and hexane can be used for stirring and pulping. The cefoperazone core obtained in this invention is a solid.

[0050] In some preferred embodiments, the method for preparing the cefoperazone nucleus includes the following steps:

[0051] 7-ACA was reacted with the active ester under alkaline conditions. The reactants were washed and then enzymatically hydrolyzed. After hydrolysis, the enzyme was removed, the carboxyl group was protected, and the mixture was purified to obtain the cefoperazone nucleus.

[0052] A second aspect of the present invention provides a method for preparing cefoperazone, comprising the following steps:

[0053] To prepare the cefbiromate nucleus, the cefbiromate nucleus was oxidized and then reacted with a nephrine salt in a Wittig reaction, followed by deprotection and reaction with the compound shown in Formula 11 to obtain the cefbiromate.

[0054] The compound shown in Formula 11 is ;

[0055] The method for preparing the cefoperazone nucleus is the same as the method described in the first aspect of this invention.

[0056] It should be noted that the neven salt (phosphorus ylide) is a zwitterionic compound with a structure of separated positive and negative charges, which can be obtained by deprotonating a quaternary phosphonium salt under strongly basic conditions. In some embodiments, the neven salt is converted to a quaternary phosphonium salt by deprotonation under strongly basic conditions, and then subjected to the Wittig reaction.

[0057] In some embodiments, the oxidation includes oxidation using inorganic hypohalates and / or manganese dioxide.

[0058] In some embodiments, the deprotection is carried out under acidic conditions. For example, deprotection is performed using trifluoroacetic acid.

[0059] In some embodiments, the oxidation is carried out in the presence of 2,2,6,6-tetramethyl-1-piperidinoxy (TEMPO).

[0060] Compared with the prior art, the beneficial effects of the present invention are:

[0061] This invention provides a method for preparing cefbiro ester nucleus. Using stable 7-ACA as the starting material, the method reacts with an active ester to acylate the 7-amino group, then removes the 3-acetyl group via enzymatic hydrolysis, and finally obtains the cefbiro ester nucleus after carboxyl protection. This preparation method is environmentally friendly, highly efficient, and yields cefbiro ester nucleus with high purity and good yield. It avoids the need for reprocessing due to the presence of certain impurities (such as Formula 12 impurities), thus improving production efficiency. Therefore, the preparation method of this invention is also applicable to the preparation of cefbiro ester. Using the cefbiro ester nucleus prepared by this invention to prepare cefbiro ester can effectively improve the purity of cefbiro ester. Attached Figure Description

[0062] Figure 1 The image shows the HPLC chromatogram of the cefoperazone core prepared in Example 1.

[0063] Figure 2 The image shows the HPLC chromatogram of the cefoperazone core prepared in Comparative Example 1. Detailed Implementation

[0064] The present invention will be further described in detail below through specific embodiments. Unless otherwise specified, the raw materials, reagents, or apparatus used in the embodiments and comparative examples are all available from conventional commercial sources or can be obtained by existing technical methods. Unless otherwise specified, the test or experimental methods are conventional methods in the art.

[0065] The following detailed description is provided in conjunction with specific embodiments and comparative examples.

[0066] The synthetic route for the cefoperazone core is as follows in the following embodiments of the present invention:

[0067] .

[0068] It should be noted that in this synthetic route, enzymatic digestion and carboxyl protection are combined into one step, meaning that the carboxyl protection step is not separately identified.

[0069] Example 1

[0070] A method for preparing cefoperazone nucleus, comprising the following steps:

[0071] 15.00 g of 7-ACA (compound of formula 4, i.e., 7-aminocephalosporanic acid) was dissolved in 150 mL of N,N-dimethylformamide. 11.1 g of triethylamine was added at 15 °C, and the mixture was stirred until dissolved. Then, 35.13 g of the active ester (compound of formula 2, where R1 is triphenylmethyl and Y is Y1) was added to the resulting solution at 0 °C–15 °C. The reaction was stirred at 0℃~15℃ for 4 hours. The reaction was confirmed to be complete by monitoring the residue of compound 4 by HPLC, and the reaction solution was obtained.

[0072] The reaction solution was diluted with 300 mL of water. The resulting aqueous layer was washed three times with 300 mL of ethyl acetate (100 mL each time). The aqueous layer was then cooled to 10 °C, and the pH was adjusted to 8.2-8.4 with 10% hydrochloric acid. The temperature was raised to 18 °C, and 15 g of deacetylesterase, 5 g of arginine, and 5 g of potassium phosphate were added. The pH was adjusted to 8.4-8.5 with 3% ammonia. The reaction temperature was controlled at 18 °C. After confirming the completeness of the reaction by monitoring the residue of compound 5 by HPLC, the solution was filtered to remove the deacetylesterase, yielding the enzymatic hydrolysate.

[0073] Dilute the enzymatic hydrolysate with 350 mL of dichloromethane and 160 mL of diazomethane solution containing 0.5 mol of diphenyldiazomethane, adjust the pH to 3 with 1 mol / L hydrochloric acid, stir at 0 °C for 2 h, and monitor the reaction to ensure complete reaction by HPLC to obtain the carboxyl protection solution (R2 is diphenylmethyl).

[0074] The carboxyl protection solution was allowed to stand to separate into layers. The organic layer was washed twice with 300 mL of cold brine, concentrated to dryness, stirred and slurried with 1250 mL of hexane, filtered, washed, and dried at 22 °C and 11 mbar for 16 h to obtain the cefoperazone core (compound of formula 3), which is a pale yellow solid.

[0075] Example 2

[0076] A method for preparing cefoperazone nucleus, which differs from Example 1 mainly in the pH of the enzymatic hydrolysis, specifically includes the following steps:

[0077] 15.00 g of 7-ACA (compound of formula 4, i.e., 7-aminocephalosporanic acid) was dissolved in 150 mL of N,N-dimethylformamide. 11.1 g of triethylamine was added at 15 °C, and the mixture was stirred until dissolved. Then, 35.13 g of the active ester (compound of formula 2, where R1 is triphenylmethyl and Y is Y1) was added to the resulting solution at 0 °C–15 °C. The reaction was stirred at 0℃~15℃ for 4 hours. The reaction was confirmed to be complete by monitoring the residue of compound 4 by HPLC, and the reaction solution was obtained.

[0078] The reaction solution was diluted with 300 mL of water. The resulting aqueous layer was washed three times with 300 mL of ethyl acetate (100 mL each time). The aqueous layer was then cooled to 10 °C. The pH was adjusted to 8.2-8.4 with 10% hydrochloric acid. The temperature was raised to 18 °C. 15 g of deacetylesterase, 5 g of arginine, and 5 g of potassium phosphate were added. The pH was adjusted to 6-8 with 3% ammonia (the pH will decrease during the reaction, so ammonia is used to neutralize the acid and adjust the pH). The reaction temperature was controlled at 18 °C. After the reaction was confirmed to be complete by HPLC monitoring of the residue of compound 5, the solution was filtered to remove the deacetylesterase, yielding the enzymatic hydrolysate.

[0079] Dilute the enzymatic hydrolysate with 350 mL of dichloromethane and 160 mL of diazomethane solution containing 0.5 mol of diphenyldiazomethane, adjust the pH to 3 with 1 mol / L hydrochloric acid, stir at 0 °C for 2 h, and monitor the reaction to ensure complete reaction by HPLC to obtain the carboxyl protection solution (R2 is diphenylmethyl).

[0080] The carboxyl protection solution was allowed to stand to separate into layers. The organic layer was washed twice with 300 mL of cold brine, concentrated to dryness, stirred and slurried with 1250 mL of hexane, filtered, washed, and dried at 22 °C and 11 mbar for 16 h to obtain the cefoperazone core (compound of formula 3), which is a dark yellow solid.

[0081] Example 3

[0082] A method for preparing cefoperazone nucleus, which differs from Example 1 mainly in the enzymatic hydrolysis temperature, specifically includes the following steps:

[0083] 15.00 g of 7-ACA (compound of formula 4, i.e., 7-aminocephalosporanic acid) was dissolved in 150 mL of N,N-dimethylformamide. 11.1 g of triethylamine was added at 15 °C, and the mixture was stirred until dissolved. Then, 35.13 g of the active ester (compound of formula 2, where R1 is triphenylmethyl and Y is Y1) was added to the resulting solution at 0 °C–15 °C. The reaction was stirred at 0℃~15℃ for 4 hours. The reaction was confirmed to be complete by monitoring the residue of compound 4 by HPLC, and the reaction solution was obtained.

[0084] The reaction solution was diluted with 300 mL of water. The resulting aqueous layer was washed three times with 300 mL of ethyl acetate (100 mL each time). The aqueous layer was then cooled to 10 °C. The pH was adjusted to 8.2-8.4 with 10% hydrochloric acid. The temperature was raised to 25-30 °C. 15 g of deacetylesterase, 5 g of arginine, and 5 g of potassium phosphate were added. The pH was adjusted to 8.4-8.5 with 3% ammonia. The reaction temperature was controlled at 25-30 °C. After confirming the completeness of the reaction by monitoring the residue of compound 5 by HPLC, the solution was filtered to remove the deacetylesterase, yielding the enzymatic hydrolysate.

[0085] Add 350 mL of dichloromethane and 160 mL of diazomethane solution containing 0.5 mol of diphenyldiazomethane to the enzymatic hydrolysate for dilution, add 1 mol / L hydrochloric acid to adjust the pH to 3, stir at 0℃ for 2 h, and monitor the reaction to ensure completeness by HPLC to obtain the carboxyl protection solution.

[0086] The carboxyl protection solution was allowed to stand to separate into layers. The organic layer was washed twice with 300 mL of cold brine, concentrated to dryness, stirred and slurried with 1250 mL of hexane, filtered, washed, and dried at 22 °C and 11 mbar for 16 h to obtain the cefoperazone core (compound of formula 3), which is a dark yellow solid.

[0087] Example 4

[0088] A method for preparing cefoperazone nucleus, which differs from Example 1 mainly in the amount of deacetylesterase used, specifically includes the following steps:

[0089] 15.00 g of 7-ACA (compound of formula 4, i.e., 7-aminocephalosporanic acid) was dissolved in 150 mL of N,N-dimethylformamide. 11.1 g of triethylamine was added at 15 °C, and the mixture was stirred until dissolved. Then, 35.13 g of the active ester (compound of formula 2, where R1 is triphenylmethyl and Y is Y1) was added to the resulting solution at 0 °C–15 °C. The reaction was stirred at 0℃~15℃ for 4 hours. The reaction was confirmed to be complete by monitoring the residue of compound 4 by HPLC, and the reaction solution was obtained.

[0090] The reaction solution was diluted with 300 mL of water. The resulting aqueous layer was washed three times with 300 mL of ethyl acetate (100 mL each time). The aqueous layer was then cooled to 10 °C, and the pH was adjusted to 8.2-8.4 with 10% hydrochloric acid. The temperature was raised to 18 °C, and 30 g of deacetylesterase, 5 g of arginine, and 5 g of potassium phosphate were added. The pH was adjusted to 8.4-8.5 with 3% ammonia. The reaction temperature was controlled at 18 °C. After confirming the completeness of the reaction by monitoring the residue of compound 5 by HPLC, the solution was filtered to remove the deacetylesterase, yielding the enzymatic hydrolysate.

[0091] Dilute the enzymatic hydrolysate with 350 mL of dichloromethane and 160 mL of diazomethane solution containing 0.5 mol of diphenyldiazomethane, adjust the pH to 3 with 1 mol / L hydrochloric acid, stir at 0 °C for 2 h, and monitor the reaction to ensure complete reaction by HPLC to obtain the carboxyl protection solution (R2 is diphenylmethyl).

[0092] The carboxyl protection solution was allowed to stand to separate into layers. The organic layer was washed twice with 300 mL of cold brine, concentrated to dryness, stirred and slurried with 1250 mL of hexane, filtered, washed, and dried at 22 °C and 11 mbar for 16 h to obtain the cefoperazone core (compound of formula 3), which is a pale yellow solid.

[0093] Example 5

[0094] A method for preparing cefoperazone nucleus, which differs from Example 1 mainly in the amount of deacetylesterase used, includes the following steps:

[0095] 15.00 g of 7-ACA (compound of formula 4, i.e., 7-aminocephalosporanic acid) was dissolved in 150 mL of N,N-dimethylformamide. 11.1 g of triethylamine was added at 15 °C, and the mixture was stirred until dissolved. Then, 35.13 g of the active ester (compound of formula 2, where R1 is triphenylmethyl and Y is Y1) was added to the resulting solution at 0 °C–15 °C. The reaction was stirred at 0℃~15℃ for 4 hours. The reaction was confirmed to be complete by monitoring the residue of compound 4 by HPLC, and the reaction solution was obtained.

[0096] The reaction solution was diluted with 300 mL of water. The resulting aqueous layer was washed three times with 300 mL of ethyl acetate (100 mL each time). The aqueous layer was then cooled to 10 °C, and the pH was adjusted to 8.2-8.4 with 10% hydrochloric acid. The temperature was raised to 18 °C, and 7.5 g of deacetylesterase, 5 g of arginine, and 5 g of potassium phosphate were added. The pH was adjusted to 8.4-8.5 with 3% ammonia. The reaction temperature was controlled at 18 °C. After confirming the completeness of the reaction by monitoring the residue of compound 5 by HPLC, the solution was filtered to remove the deacetylesterase, yielding the enzymatic hydrolysate.

[0097] Dilute the enzymatic hydrolysate with 350 mL of dichloromethane and 160 mL of diazomethane solution containing 0.5 mol of diphenyldiazomethane, adjust the pH to 3 with 1 mol / L hydrochloric acid, stir at 0 °C for 2 h, and monitor the reaction to ensure complete reaction by HPLC to obtain the carboxyl protection solution (R2 is diphenylmethyl).

[0098] The carboxyl protection solution was allowed to stand to separate into layers. The organic layer was washed twice with 300 mL of cold brine, concentrated to dryness, stirred and slurried with 1250 mL of hexane, filtered, washed, and dried at 22 °C and 11 mbar for 16 h to obtain the cefoperazone core (compound of formula 3), which is a pale yellow solid.

[0099] Comparative Example 1

[0100] A method for preparing cefoperazone core, the synthetic route is as follows:

[0101]

[0102] Note: The carboxyl protection step is not shown in the synthetic route, but carboxyl protection was performed during the synthesis process to introduce the R2 carboxyl protecting group.

[0103] Specifically, the following steps are included:

[0104] 15.00 g of D-7ACA (compound of formula 1) was added to 150 mL of N,N-dimethylformamide, and 8.2 mL of 1,1,3,3-tetramethylguanidine was added at 15 °C. The mixture was stirred until dissolved. 35.13 g of the active ester (compound of formula 2, where R1 is triphenylmethyl and Y is Y1) was added to the resulting solution at 0 °C. The reaction was continued at 0℃ for 4 hours with stirring. HPLC monitoring of the residue of compound 1 confirmed the complete reaction. The solution was diluted with 300 mL of water, and the aqueous layer was washed three times with 300 mL of ethyl acetate (100 mL each time). A solution of 350 mL dichloromethane and 160 mL 0.5 mol diphenyldiazomethane in diazomethane was added for dilution. The pH was adjusted to 3 with 1 mol / L hydrochloric acid, and the mixture was stirred at 0℃ for 2 hours. HPLC monitoring confirmed the complete reaction. The layers were separated. The organic layer was washed twice with 300 mL of cold brine, dried over MgSO4, filtered, and the filtrate was diluted with 2700 mL of hexane, resulting in a gelatinous precipitate. The supernatant was discarded, and the mixture was stirred and slurried with 1250 mL of hexane, filtered, washed, and dried at 22℃ and 11 mbar for 16 hours to obtain a pale yellow solid of cefoperazone core (compound 3).

[0105] Comparative Example 2

[0106] A method for preparing cefoperazone nucleus, which differs from Example 1 mainly in that arginine and potassium phosphate are not added, specifically includes the following steps:

[0107] 15.00 g of 7-ACA (compound of formula 4) was dissolved in 150 mL of N,N-dimethylformamide. 11.1 g of triethylamine was added to the solution at 15 °C, and the mixture was stirred until dissolved. Then, 35.13 g of the active ester (compound of formula 2, where R1 is triphenylmethyl and Y is Y1) was added to the resulting solution at 0 °C–15 °C. The reaction was stirred at 0℃~15℃ for 4 hours. The reaction was monitored by HPLC until it was complete, and the reaction solution was obtained.

[0108] The reaction solution was diluted with 300 mL of water. The aqueous layer was washed three times with 300 mL of ethyl acetate (100 mL each time). The aqueous layer was then cooled to 10 °C. The pH was adjusted to 8.2-8.4 with 10% hydrochloric acid. The temperature was raised to 18 °C. 15 g of deacetylesterase was added. The pH was adjusted to 8.4-8.5 with 3% ammonia. The reaction temperature was controlled at 18 °C. After the reaction was completed, the solution was filtered to remove the deacetylesterase, and the enzymatic hydrolysate was obtained.

[0109] Dilute the enzymatic hydrolysate with 350 mL of dichloromethane and 160 mL of diazomethane solution containing 0.5 mol of diphenyldiazomethane, adjust the pH to 3 with 1 mol / L hydrochloric acid, and continue stirring at 0 °C for 2 h. Monitor the reaction by HPLC to ensure complete reaction and obtain the carboxyl-protected solution (R2 is diphenylmethyl).

[0110] The carboxyl-protecting solution was allowed to stand to separate into layers. The organic layer was washed twice with 300 ml of cold brine, concentrated to dryness, and stirred with 1250 mL of hexane. After filtration and washing, the solution was dried at 22 °C and 11 mbar for 16 h to obtain a pale yellow solid of cefoperazone core (compound of formula 3).

[0111] Application Example 1

[0112] A method for preparing cefoperazone, the synthetic route is as follows:

[0113]

[0114] Specifically, the following steps are included:

[0115] The cefoperazone core was prepared using the same preparation method as in Example 1;

[0116] 22.47 g of cefoperazone nucleus (compound of formula 3) was added to 110 mL of dichloromethane to form a suspension, and then 70 mL of aqueous solution containing 369 mg KBr and 958 mg NaHCO3 was added to form a mixture. The mixture was cooled to 0 °C, and 2 mL of dichloromethane solution containing 391 mg TEMPO (2,2,6,6-tetramethyl-1-piperidinoxy) was added. Then, 29 mL of aqueous solution of NaOCl (9.93% by mass) was added under vigorous stirring, and stirring was continued for 2 h. The reaction was monitored by HPLC to ensure complete reaction, and the reaction mixture was obtained.

[0117] The reaction mixture was filtered, the organic layer was washed with brine, and then treated with MgSO4 and charcoal in sequence (stirring after adding the organic layer). After filtration, the filtrate was stirred with 25g of silica for 10min, filtered, and the filtrate was evaporated to dryness to obtain 16.61g of compound 7.

[0118] At -30°C, over 5 min, a mixed solution of 6.0 mL of dichloromethane and 6.0 mL of toluene containing 1.22 g (1.875 mmol) of compound 8 ([(3R)-1-[(1,1-dimethylethoxy)carbonyl]-2-oxo-[1,3-bipyrrolidine]-3-yl]triphenylphosphine bromide) was added to a solution containing 0.195 g (1.732 mmol) of t-C4H9OK (potassium tert-butoxide). The mixture was stirred at -30°C for 45 min. Then, over 5 min, a solution of 3.0 mL of tetrahydrofuran containing 1.008 g (1.249 mmol) of compound 7 was added to the resulting solution. The mixture was stirred at -30°C for another 45 min. The reaction was terminated with 10% citric acid. The product was extracted with ethyl acetate and evaporated to dryness.

[0119] The product obtained by evaporation was added to 13.8 mL of ethyl acetate. The resulting suspension was stirred at 5 °C for 0.5 h, then centrifuged. The product was washed and purified with a 1:1 volume ratio of dichloromethane and ethyl acetate mixture and dried under vacuum to obtain compound 9.

[0120] A 25 mL dichloromethane suspension containing 5.785 g of compound 9 and 1.69 mL of triethylsilane was added to 7.21 mL of trichloroacetic acid at -15 °C, heated to 30 °C, and stirred for 30 min. The reaction was monitored by HPLC until complete. The resulting mixture was then evaporated to dryness, and the residue was digested with 60 mL of ethyl acetate. The suspension was filtered, and the residue was dried to give 3.43 g of compound 10 as a brown solid.

[0121] Add 800 g of dimethyl sulfoxide to the reaction flask, start stirring, add 58 g of compound 11 at room temperature, stir until dissolved, add 100 g of compound 10, keep warm and stir for 2 h, add 2 g of sodium isooctanoate, stir and react at room temperature for 24 h, after the reaction is complete, add 200 g of acetone, stir to precipitate crystals, filter, wash with 50 g of acetone, and dry under vacuum to obtain cefoperazone (compound 5), the purity of which was 95.3% as determined by HPLC.

[0122] Comparative Application Example 1

[0123] A method for preparing cefoperazone, the synthetic route is the same as in Application Example 1, and the specific steps are as follows:

[0124] The cefoperazone core was prepared using the same preparation method as in Comparative Example 1;

[0125] 22.47 g of cefoperazone nucleus (compound of formula 3) was added to 110 mL of dichloromethane to form a suspension, and then 70 mL of aqueous solution containing 369 mg KBr and 958 mg NaHCO3 was added to form a mixture. The mixture was cooled to 0 °C, and 2 mL of dichloromethane solution containing 391 mg TEMPO (2,2,6,6-tetramethyl-1-piperidinoxy) was added. Then, 29 mL of aqueous solution of NaOCl (9.93% by mass) was added under vigorous stirring, and stirring was continued for 2 h. The reaction was monitored by HPLC to ensure complete reaction, and the reaction mixture was obtained.

[0126] The reaction mixture was filtered, the organic layer was washed with brine, and then treated with MgSO4 and charcoal in sequence. After filtration, the filtrate was stirred with 25g of silica for 10min, filtered, and the filtrate was evaporated to dryness to obtain 16.61g of compound 7.

[0127] At -30°C, over 5 min, a solution of 6.0 mL of tetrahydrofuran containing 0.195 g (1.732 mmol) t-C4H9OK (potassium tert-butoxide) was added to a mixed solution of 6.0 mL of dichloromethane and 6.0 mL of toluene containing 1.22 g (1.875 mmol) of compound 8. The mixture was stirred at -30°C for 45 min. Then, over 5 min, a solution of 3.0 mL of tetrahydrofuran containing 1.008 g (1.249 mmol) of compound 7 was added to the resulting solution. The mixture was stirred at -30°C for another 45 min. The reaction was terminated with 10% citric acid. The product was extracted with ethyl acetate and evaporated to dryness.

[0128] The product obtained by evaporation was added to 13.8 mL of ethyl acetate, and then DMSO (dimethyl sulfoxide) was added dropwise over 15 min. The mixture was stirred until the evaporated product dissolved, and then stirred until a solid precipitated. Ethyl acetate was then added to obtain a suspension, which was stirred at 0 °C to 5 °C for 0.25 h. The suspension was filtered, washed with a small amount of ethyl acetate, and the washed product was dissolved in dichloromethane at 23 to 27 °C. The product was crystallized and purified, and then 13.8 mL of ethyl acetate was added. The mixture was stirred at 5 °C for 0.5 h, centrifuged, and then washed with a 1:1 mixture of dichloromethane and ethyl acetate. The product was then dried under vacuum to obtain compound 9.

[0129] A 25 mL dichloromethane suspension containing 5.785 g of compound 9 and 1.69 mL of triethylsilane was added to 7.21 mL of trichloroacetic acid at -15 °C, heated to 30 °C, and stirred for 30 min. The reaction was monitored by HPLC until complete. The resulting mixture was then evaporated to dryness, and the residue was digested with 60 mL of ethyl acetate. The suspension was filtered, and the residue was dried to give 3.43 g of compound 10 as a brown solid.

[0130] Add 800 g of dimethyl sulfoxide to the reaction flask, start stirring, add 58 g of compound 11 at room temperature, stir until dissolved, add 100 g of compound 10, keep warm and stir for 2 h, add 2 g of sodium isooctanoate, stir and react at room temperature for 24 h, after the reaction is complete, add 200 g of acetone, stir to precipitate crystals, filter, wash with 50 g of acetone, and vacuum dry to obtain cefoperazone (compound 5), the purity of which was 88.2% as determined by HPLC.

[0131] Result detection

[0132] 1. Yield of cefoperazone core

[0133] Based on the amount of 7-ACA or D-7ACA used in the examples and comparative examples, the theoretical mass of the cefbiloprotein core was calculated, and the yield was calculated in combination with the actual mass of the cefbiloprotein core: yield = actual mass ÷ theoretical mass × 100%.

[0134] The results are shown in Table 1.

[0135] Table 1. Yield of cefoperazone core

[0136]

[0137] 2. Purity of cefoperazone nucleus

[0138] The purity of the cefoperazone cores obtained in Example 1 and Comparative Example 1 was determined by high-performance liquid chromatography (HPLC). The results are shown in Table 2 and... Figures 1-2 .

[0139] Table 2. Purity of cefoperazone nucleus in Example 1 and Comparative Example 1

[0140]

[0141] In Table 1, the impurities in Formula 12 are... Formula 13 impurities are .

[0142] Figure 1 and Figure 2 The images show the HPLC chromatograms of the cefoperazone core prepared in Example 1 and Comparative Example 1, respectively. Figure 1 , Figure 2 As can be seen from Table 1, the cefoperazone nucleus prepared by the new synthesis process in Example 1 of this invention has a higher purity, reaching 98.4%, while the purity of Comparative Example 1 is only 93.1%. Furthermore, the cefoperazone nucleus obtained in Example 1 of this invention does not contain the impurities shown in Formula 12, and the content of impurities in Formula 13 is also lower, avoiding the problem of reduced production efficiency caused by the presence of specific impurities such as Formula 12 or Formula 13 requiring refining processes.

[0143] in, Figure 2 The retention time and peak area are shown in Table 3 below.

[0144] Table 3. HPLC retention time and peak area of ​​cefoperazone core in Comparative Example 1

[0145]

[0146] Furthermore, as can be seen from Application Example 1 and Comparative Application Example 1, the preparation of cefbiloridine core using the preparation method of the present invention, and its subsequent use in the preparation of cefbiloridine, significantly simplifies the purification process of the intermediate compound of Formula 9. This also demonstrates that the cefbiloridine core obtained by the present invention has higher purity, and its use in the preparation of cefbiloridine not only helps to improve the purity of cefbiloridine, but also simplifies the production steps and improves production efficiency.

[0147] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for preparing cefoperazone nucleus, characterized in that, Includes the following steps: 7-ACA was reacted with the active ester under alkaline conditions. After enzymatic hydrolysis and carboxyl protection, the cefoperazone nucleus was obtained. The cefoperazone core has the structure shown in Formula 3: ； Wherein, R1 is triphenylmethyl and R2 is diphenylmethyl; The active ester has the structure shown in Formula 2: Wherein, R1 is triphenylmethyl, and Y is Y1: ; The enzyme used in the enzymatic hydrolysis process is deacetylesterase; arginine and potassium phosphate are also added during the enzymatic hydrolysis process. The alkaline conditions are provided by an alkaline solvent, which is triethylamine.

2. The preparation method according to claim 1, characterized in that, The mass ratio of the deacetylesterase, arginine, and potassium phosphate is (1~6):1:

1.

3. The preparation method according to claim 1, characterized in that, The mass ratio of the enzyme used in the enzymatic hydrolysis to the 7-ACA is (0.5~2):

1.

4. The preparation method according to claim 1, characterized in that, The pH of the enzymatic hydrolysis is 6-9.

5. The preparation method according to claim 1, characterized in that, The enzymatic hydrolysis temperature is 10~25℃.

6. The preparation method according to claim 1, characterized in that, The reaction of 7-ACA with the active ester satisfies at least one of the following reaction conditions: a) The reaction temperature is 0~15℃; b) The reaction solvent is N,N-dimethylformamide.

7. The preparation method according to claim 1, characterized in that, After the 7-ACA reacts with the active ester, a washing step is also included: the solution obtained after the reaction is diluted with water, and the aqueous layer is washed with ethyl acetate.

8. The preparation method according to claim 1, characterized in that, The carboxyl protection includes the following steps: mixing the product obtained from the enzymatic hydrolysis with an organic solvent and a carboxyl protecting agent, reacting to complete the carboxyl protection; the organic solvent is dichloromethane; the carboxyl protecting agent is diphenyldiazomethane.

9. The preparation method according to claim 8, characterized in that, After carboxyl protection, the product is further purified by separating the carboxyl-protected product into layers, washing and concentrating the organic layer, stirring and slurrying, filtering, washing and drying to obtain the cefoperazone nucleus.

10. A method for preparing cefoperazone, characterized in that, Includes the following steps: To prepare the cefbiromate nucleus, the cefbiromate nucleus was oxidized and then subjected to a Wittig reaction with a nemonin salt, followed by deprotection and acylation with the compound shown in Formula 11 to obtain the cefbiromate. The compound shown in Formula 11 is ; The method for preparing the cefoperazone nucleus is the method described in any one of claims 1 to 9.

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