PREPARATION METHOD OF 7-ALPHA-METHOXY-CEPHALOSPORANIC ACID DERIVATIVE

摘要

PURPOSE: A preparation method of 7-alpha-methoxy-cephalosporanic acid derivative is provided. Thereby, 7-alpha-methoxy-cephalosporanic acid derivative is simply prepared in high yield not using reagent containing heavy metal. Therefore, it can prevent environment pollution. CONSTITUTION: A preparation method of 7-alpha-methoxy-cephalosporanic acid derivative of the formula (4) or (5) is characterized by comprising the following steps of: (i)putting 7-sulfeneiminocephalosporanic acid derivative of the formula (2) or 7-sulfeneiminocephalosporanic acid diphenyl diazomethane(DPM)ester of the formula (3) in methylenechloride solution and adding 0.5-10 equivalent of triphenyl-phosphine; (ii)adding 0.5-5 equivalent of an aluminium halide which is dissolved in anhydrous methanol. The aluminium halide is characterized by aluminium chloride. In the formula (1), R' is alkyl or aryl gorup having 1-7 of carbons; R is OCOCH3 or STz((1-methyl-1H-tetrazol-5-yl)thio) group; X is dicyclohexylamine.