Cephalosporins having at position-7 a carboxy substituted α-etherified hydroxyimino-arylacetamido group and at position-3 the residue of a sulphur nucleophile

Abstract

Abstract Cephalosporin antibiotics having the formula: ##STR1## (where R is thienyl, furyl or phenyl; R a is hydrogen, C 1-4 alkyl, C 2-4 alkenyl, C 3-7 cycloalkyl or phenyl, and R b is hydrogen, C 1-4 alkyl, C 2-4 alkenyl, C 3-7 cycloalkyl, phenyl, carboxy or C 2-5 alkoxycarbonyl, or R a and R b together with the carbon atom to which they are attached form a C 3-7 cycloalkylidene or cycloalkenylidene group; R 13 is C 1 -C 6 alkyl, C 3-7 cycloalkyl, phenylalkyl, phenyl or naphthyl, thiadiazolyl, diazolyl, triazolyl, tetrazolyl, thiazolyl, thiatriazolyl, oxazolyl, oxadiazolyl, pyridyl, pyrimidyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, triazolopyridyl or purinyl, and n is 0, 1 or 2 and their physiologically acceptable derivatives exhibit broad spectrum antibiotic activity characterized by particularly high activity against gram negative microorganisms, including those which produce β-lactamases. The compounds, which are syn isomers or exist as mixtures of syn and anti isomers containing at least 90% of the syn isomer, have particularly high in vitro activity against strains of Escherichia coli, Haemophilus influenzae and Proteus organisms; and unusually high activity against Pseudomonas organisms.

Inventors

• 👤 Janice Bradshaw
• 👤 Martin C. Cook
• 👤 Gordon I. Gregory

Bibliographic Details