2-(heterocyclylthio) carbapenem derivatives, their preparation and their

Abstract

Compounds of formula (I): ##STR1## in which R.sup.a is a group of formula (II): ##STR2## where one of R' is a bond to the remainder of the compound, one more of R' is R.sup.2 and the others of R' are all hydrogen, R.sup.1 is hydrogen or methyl, R.sup.2 is hydrogen, optionally substituted alkyl, halogen, hydroxy, alkoxy, amino, alkanoylamino, alkanoyloxy, alkanoyl, carboxy, alkoxycarbonyl, cyano, --S(O).sub.j R.sup.9 where j is 0, 1 or 2 and R.sup.9 is alkyl, or --CONR.sup.6 R.sup.7 which is optionally substituted carbamoyl or heterocyclyl-carbonyl, --NR.sup.3 R.sup.4 is optionally substituted amino or heterocyclic, and --COOR.sup.5 is carboxy, --COO.sup.-, --COOM.sub.x, where M is a cation and x is the reciprocal of the valence of the cation M or protected carboxy and, where --COOR.sup.5 is carboxy, --COOM.sub.x or protected carboxy, the compound of formula (I) also contains an anion; l, m and n are independently 0, 1, 2 or 3, provided that (m+n) is an integer from 2 to 6; p is 0, 1 or 2; Y is a single bond, oxygen, sulfur or ##STR3## wherein R.sup.8 is hydrogen, alkyl or alkanoyl, and pharmaceutically acceptable salts and esters thereof. Such compounds are useful as antibiotics.