Process for refining cefmetazole sodium

摘要

The present invention relates to a novel process for refining Cefmetazole sodium, comprising the steps of: 1) dissolving Cefmetazole sodium material in water, and extracting after adding a water-immiscible organic solvent(s), followed by separating the organic phase containing impurities, to provide an aqueous phase containing Cefmetazole sodium; 2) treating by adding an alkoxide of alkali metal or alkaline earth metal into the above aqueous phase, followed by filtrating the precipitate, to provide an aqueous filtrate; and 3) adding ethanol or acetone in the aqueous solution and recrystallizing, followed by centrifuging and washing the resultant crystals, to provide the refined and purified Cefmetazole sodium after drying. The purity of Cefmetazole sodium material can be greatly improved by the process of the present invention.

主权项

1. A process for refining Cefmetazole sodium, characterized in that, it comprises the steps of:
1) dissolving Cefmetazole sodium-contained raw material in water, and extracting after adding a water-immiscible organic solvent(s) selecting from a group consisting of ethyl acetate, cyclohexane, and a mixture of ethyl acetate and cyclohexane, followed by separating the organic phase containing impurities, to provide a primarily purified Cefmetazole sodium in the aqueous phase; 2) treating by adding an alkoxide of alkali metal or alkaline earth metal into the above aqueous phase, optionally under heating during the treating process, followed by cooling down and filtrating the precipitate to provide a filtrate, which is a secondarily purified Cefmetazole sodium aqueous solution; and 3) adding in the aqueous solution a solvent selecting from a group consisting of ethanol, acetone and a mixture of ethanol and acetone, and recrystallizing by decreasing the temperature until it reaches between room temperature and −5° C., followed by centrifuging and washing the resultant crystals, to provide a thirdly purified Cefmetazole sodium after drying.