PROCESS OF PRODUCING CEPHALOSPORIN AND DERIVATIVES

摘要

Phosphoramidopenicillanates, which are starting materials for manufg. cephalosporinn deriv., were dehydrated with MeSO3H or Cl2CHPO3H2-pyridine by refluxing in dioxane or dichloroethane-DMF to give 7-amino-3-desacetoxycephalosporanic acids, which underwent dephosphorylation with phosgene to give isocyanato-cephemcarboxylates (I; R = ester protecting group) which are useful as a broad spectrum antibiotic.