Synthesis and Antibacterial Activity of New Cephalosporins with Lactonyloxyimino Moiety

A series of $7-{2-(aminothiazol-4-yl)-2-Z-({\gamma}-lacton-3-yl)oxyiminoactamido}$ cephalosporins with various substituents at the 30position in cephem nucleus in cephem nucleus were synthesized and evaluated microbiologically. The tested compounds showed potent activities but were somewhat less active than cefotaxime or cefixime against a wide variety of Gram-positive and Gram-negative bacteria.