Abrégé

Disclosed is a continuous preparation method for ceftazidime, which comprises the following steps: S1, preparing a ceftazidime dihydrochloride solution; S2, preparing a sodium hydroxide solution; S3, preparing a phosphoric acid solution; S4, adding the ceftazidime dihydrochloride solution and the sodium hydroxide solution into a high-speed centrifugal mixer at a certain flow for rapid mixing, respectively, and then enabling the mixed solution to flow out of an outlet of the high-speed centrifugal mixer to obtain a ceftazidime solution 1; S5, adding a mixing suspension solution of a ceftazidime seed crystal and water into a crystallizer A, and continuously adding the ceftazidime solution 1 and the phosphoric acid solution at a constant speed; S6, when the volume of a crystallized solution in the crystallizer A exceeds 100 mL, allowing the crystallized solution to automatically overflow from the crystallizer A and flow into a crystallizer B, and growing a crystal in the crystallizer B for a period of time, filtering, washing, and drying same to obtain a ceftazidime product. According to the present invention, the impurity content, especially the impurity content of RRT = 0.82, can be significantly reduced, the purity is improved, and the particle size of a powder is uniform.

Classes IPC  ?

• C07D 501/12 - SéparationPurification
• C07D 501/46 - Radicaux méthylène, substitués par des atomes d'azoteLeurs lactames avec le groupe carboxyle-2Radicaux méthylène substitués par des hétérocycles contenant de l'azote lié par l'atome d'azote du cycleLeurs composés quaternaires avec le radical amino-7 acylé par des acides carboxyliques contenant des hétérocycles

Abrégé

A method for refining cefotaxime sodium, comprising the following steps: (1) dissolving cefotaxime acid in a mixed solvent of water, methanol, and acetone, adding sodium acetate, and stirring to dissolve until clarification; (2) adding activated carbon, stirring, and then filtering; and (3) rapidly adding ethyl acetate to a filtrate under strong turbulence, the strong turbulence having a Reynolds number of 11,000 or more; (4) performing crystal growing under mild turbulence, the mild turbulence having a Reynolds number reaching 4,000-6,000; (5) slowly adding ethyl acetate under rapid turbulence and continuously performing the crystal growing, the rapid turbulence having a Reynolds number reaching 6,500-8,000; and (6) after the crystal growing is finished, filtering, washing, and vacuum-drying to obtain the cefotaxime sodium. The method adopts rapid turbulence for crystallization and uses various solvents, which can increase the solubility of different impurities and reduce impurities entrained in crystals, thereby improving the product quality.

Classes IPC  ?

• C07D 501/34 - Radicaux méthylène substitués par des atomes d'oxygèneLeurs lactones avec le groupe carboxyle-2 avec le radical amino-7 acylé par des acides carboxyliques contenant des hétérocycles
• C07D 501/12 - SéparationPurification