39 results about "Phenylglycine methyl ester" patented technology

The invention discloses a method for preparing cephradine. Under the catalysis of enzymes, 7-ADCA and dihydrophenylglycine methyl ester are reacted in an enzyme-catalyzed reactor equipped with a two-phase system to form cephradine. The lower phase is separated and filtered to remove cephradine, and the mother liquor is returned to the enzyme-catalyzed reactor for circular reaction. The present invention adopts enzymatic method to synthesize cephradine, less solvent is used, the pollution to the environment is reduced, the two-phase system is adopted, the products inhibiting the reaction and some by-products can be separated in time during the reaction process, and the synthesis reaction and the product can be realized The separation cycle is carried out, thereby greatly improving the conversion rate of the reaction.

The invention discloses a penicillin G acylation enzyme mutant, and application thereof in synthesis of cephalosporin antibiotics. An amino acid sequence of the penicillin G acylation enzyme mutant is shown in SEQ ID NO.1; a nucleotide sequence of an encoding gene is shown in SEQ ID NO.2. The invention also provides application of the penicillin G acylation enzyme mutant in synthesis of cefaclor. The invention provides a novel penicillin acylation enzyme mutant. Compared with the wild penicillin acylation enzyme mutant, the penicillin G acylation enzyme mutant has higher activity in synthesis of cephalosporin antibiotics, such as cefprozil, cefaclor or cefadroxil; especially when the penicillin G acylation enzyme mutant is used for catalyzing 7-ACCA and phenylglycine methyl ester to synthesize the cefaclor, the vitality is improved to 29.8U / mg from 1.2U / mg in the past, the synthesis and hydrolysis activity is almost consistent with that of the wild penicillin acylation enzyme mutant, the synthesis and hydrolysis ratio can be up to 1.7, and the yield of the cefaclor can be up to 71.5%.

The invention discloses a method for preparing cefaclor from an enzyme process. The method comprises the following steps: preparing cefaclor coarse powder from 7-amino-3-chloro-cephem acid, D-o-phenylglycine methyl ester hydrochloride, immobilized cefaclor synthetase and cefaclor crystal seed; dissolving and discoloring the cefaclor coarse powder, adding the cefaclor crystal seed to regulate the pH value, stirring for a first time to grow the grains, and stirring for a second time to grow the grains after regulating the pH value, thereby preparing a crystal mixed solution; performing the suction filtration on the crystal mixed solution to obtain a crystal product and crystallized mother liquor; and sequentially performing washing with water, soaking washing, suction filtration and vacuum drying on the crystal product to obtain cefaclor. The method for preparing cefaclor from the enzyme process has twice stirring grain-growing operation, and the cefaclor slowly separates out in a re-crystallizing process, and the prepared crystal is uniform and is better in crystalline form; and the prepared cefaclor has very high purity greater than 99.7%.

The invention belongs to the technical field of the chemical industry, and in particular relates to a preparation process of D-phenylglycine methyl ester hydrochloride crystals. The preparation process comprises the following steps: sequentially adding methanol and D-phenylglycine into a reactor, stirring uniformly, and slowly adding sulfoxide chloride; controlling the temperature in the reactor below 55DEG C, and controlling the temperature in the reactor to be 55-65DEG C after adding sulfoxide chloride; performing reflux reaction, then performing vacuum azeotropic distillation, and finally performing temperature controlled cooling crystallization; and filtering, washing and drying to obtain a D-phenylglycine methyl ester hydrochloride crystal product. The preparation process provided by the invention is high in one-pass yield, the prepared product is high in purity, good in color grade and stable in quality, the preparation process is low in production cost, and the operation is easy to control.