abstract |
Disclosed are compounds of the general formula: ##STR1## wherein R 1 is amino, an acylated amino or a protected amino group, X is hydrogen or methoxy, and R' is hydrogen, R or R 4 wherein R is an organic residue attached to the azetidine ring through a carbon atom therein and R 4 is azido, a halogen, an amino group which may optionally be acylated or a group of the formula --OR 5 , ##STR2## or --S--S--R 5 wherein R 5 is an organic residue and n is 0, 1 or 2, and pharmaceutically acceptable salts and esters thereof. n The compounds have antimicrobial and/or β-lactamase-inhibitory activity and are of value as drugs for human beings and domesticated animals. |