SYNTHESIS AND BIOLOGICAL PROPERTIES OF SOME 3-[(N-SUBSTITUTED-AMINO)PYRIDINIUM-4-THIOMETHYL]-7-[2-(2-AMINO-THIAZOL-4-YL)-2-(Z)-(METHOXYIMINO)ACETAMIDO]CEPH-3-EM-4-CARBOXYLATES

The synthesis and antibacterial activity of a series of beta-lactamase stable, broad spectrum 7-[2-(2-amino-thiazol-4-yl)-2-(Z)-(methoxyimino)acetamido]-cephalosporins, characterised by a C-3-[N-(substituted-amino)pyridinium-4-thiomethyl] group, is described. Gram-positive and Gram-negative bacteria including extended spectrum beta-lactamase-producing strains were most susceptible to the N-amino- and N-methylamino derivatives (3a) and (3b); with the exception of Pseudomonas aeruginosa, (3b) was more active in vitro and in vivo than cefpirome or ceftazidime.