| abstract |
Antibiotic penem compounds of formula (I), wherein R represents a physiologically hydrolyzable group, forming esters and useful in the penem compound. This group is a group easy to remove by hydrolysis in vivo, for example an acetyloxymethyl group, 1- (acetyloxy) ethyl, pivaloyloxymethyl, 1- (ethoxycarbonyloxy) ethyl, 1- (isopropyloxycarbonyloxy) ethyl, 1- (cyclohexy oxycarbonyloxy) ethyl or 3-phthalidyl. Oral antibiotic compositions are also described. |