CEPHALOSPORIN DERIVATIVE PRODUCTION BY A 7 ALPHA-METHOXYLATION PROCESS AND INTERMEDIATES

摘要

A new, efficient process is provided for the production of 7 beta -[(2D-2-amino-2-carboxy)-ethylthioacetamido]- 7 alpha -methoxy-3-[(1-methyl-1H-tetrazole-5-yl)thiomethyl]-3-cephem-3-carboxylic acid which is useful as an antibacterial agent. This process is economic in using as the starting material the inexpensive, corresponding cephem compound containing no 7 alpha -methyoxy group on the cephem nucleus and comprises 7 alpha -methoxylation of a protected derivative of the starting cephem compound with t-butyl hypochlorite and lithium methoxide, followed by inactivation of the excess methoxylation reagents with a trialkyl phosphite and acetic acid to prevent undesired side-reactions such as oxidation of the alkyl-thioacetyl group of the product, and further by conventional removal of the protecting groups.