7-(N-substituted-2-phenylglycinamido)-3-substituted-3-cephem-4-carboxylic acid compounds and preparation thereof

摘要

New cephalosporin compounds of the formula: <IMAGE> (1) wherein R1 is hydrogen or hydroxy, R2 is a substituted alkanoyl group, R3 is hydrogen, carbamoyloxy, alkanoyloxy or a heterocyclic-thio group which may have suitable substituents, and R4 is carboxy or protected carboxy.