Intermediates for cyclobutenedione substituted (1-carba)cephalosporin compounds

Abstract

A compound of formula I ##STR1## wherein X is sulfur or CH.sub.2 ; R.sup.1 is hydrogen, hydroxy, amino, C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, phenyl optionally substituted with one to three C.sub.1-6 alkyl, C.sub.1-6 alkyloxy or hydroxy, C.sub.1-6 alkylthio, phenylthio optionally substituted with one to three C.sub.1-6 alkyl or C.sub.1-6 alkyloxy on the phenyl ring, phenylmethyloxy optionally substituted with one to three C.sub.1-6 alkyl or C.sub.1-6 alkyloxy on the phenyl ring, 1-morpholino, C.sub.1-6 alkyloxy, C.sub.2-6 alkenylmethyloxy, C.sub.3-6 alkynylmethyloxy, C.sub.1-6 alkylamino, C.sub.1-6 dialkylamino or a radical selected from the group consisting of ##STR2## in which n is 0 to 3, R.sup.5 is C.sub.1-6 alkyl or hydrogen, and R.sup.3 and R.sup.4 are independently C.sub.1-6 alkyl; R.sup.2 is hydrogen, a conventional amino protecting group or an acyl group; R.sup.0 is hydrogen or a conventional carboxy protecting group, or --CO.sub.2 R.sup.0 taken together forms a physiologically hydrolyzable ester; or pharmaceutically acceptable salts or solvates thereof.

Dependencies are inferred from the claim text.