Novel cephalosporin compounds, a process for the preparation thereof, pharmaceutical compositions containing the same and the use thereof as a therapeutic agent against a microorganism

The present invention relates to cephalosporins of the formula wherein R represents an aromatic or hetero aromatic group, R and R represents optionally substituted alkyl, aryl, or aralkyl, a heterocyclic group, or a group of the formula -OR , wherein R represents hydrogen, a salt forming cation optionally substituted alkyl, aryl, or aralkyl, or a heterocyclic group, or R and/or R represent(s) a group of the formula -NR R , wherein R and R represents hydrogen, optionally substituted alkyl or aryl or a cycloalkyl group, or R and R form a heterocyclic ring, or R and R form a heterocyclic ring, R represents hydrogen, a salt forming cation, or an ester forming group, and R repre-sents hydrogen, acyloxy, carbamoyloxy, optionally substituted pyridyl, or a group of the formula -SR , wherein R represents alkyl or a heterocyclic group, and salts thereof. The above cephalosporins show antibiotic properties.