Patent ID: 6555680
Filing Date: 2003-04-29
Classification: C07D

Abstract:
A process for preparing Ceftiofur sodium of formula (I) said process comprising the steps of:(a) condensing 3-[2-(furylcarbonyl)thiomethyl]-3-cephem-4-carboxylic acid represented by formula (II) with 5-phenyl-1,3,4-oxadiazole-2-thio-2-(2-aminothiazol-4-yl)2-methoxyimino)acetate represented by formula (III) in a mixture of water and an organic solvent, in the presence of an amine base at a pH range of 7.0 to 8.5 an at a temperature between âˆ’25Â° C. and 30Â° C. and subsequent extraction with a solvent selected from dichloromethane or ethylacetate, to obtain Ceftiofur amine salt in aqueous phase,(b) treating the aqueous solution of Ceftiofur amine salt of step (a) with charcoal, filtering and evaporating the aqueous solution by employing an evaporation technique under vacuum to remove water to yield a slurry of Ceftiofur amine salt, and (c) treating the slurry of step (b) containing Ceftiofur amine salt with sodium base and precipitating and isolating Ceftiofur sodium by adding organic solvent, followed by filtering the precipitated solid and drying the filtered solid.