Cephalosporins, processes for producing the same, intermediates thereof and process for producing the intermediates

Abstract From the Canadian patent

Novel cephalosporins which has attached to the exomethylene group at the 3-position of the cephem ring a substituted or unsubstituted aryl, acylamino aromatic, heterocyclic, triazolyl or tetrazolyl group said, aromatic heterocyclic group being attached through a carbon-carbon bond and said triazolyl or tetrazolyl group being attached through a carbon-nitrogen bond and has the following group attached to the amino group at the 7-position:, wherein A represents a group of the formula -CH2- or a group of the formula , in which R5 represents a hydrogen atom or an alkyl group and, the bond ? represents syn or anti isomer or their mixture; R3 represents a hydrogen or halogen atom; and R …