Abstract: Novel cephem derivatives represented by the general formula ##STR1## in which the Acyl substituent is a group of the formula ##STR2## wherein Ar is a lipophilic optionally substituted phenyl, naphthyl or pyridyl group; R.sup.1 represents either the residue of a heterocyclic amino acid or a C.sub.2 -C.sub.10 alkyl group substituted by both a carboxyl group and a group of the formula --NR.sup.9 R.sup.10 or ##STR3## in which R.sup.9 and R.sup.10 are each independently hydrogen or C.sub.1 -C.sub.6 alkyl, said C.sub.2 -C.sub.10 alkyl group being optionally interrupted by one or more nitrogen atoms or carbonyl groups, and R.sup.2 and R.sup.3 are each independently hydrogen, alkyl or aminoalkyl are gram-positive antibacterial agents, especially useful in the treatment of diseases caused by methicillin-resistant Staphylococcus aureus (also referred to below as MRSA or methicillin-resistant S. aureus).

Abstract: Certain novel biaryl compounds are effective phospholipase A.sub.2 (PLA.sub.2) inhibitors.

Abstract: There is described the stereoselective total synthesis by a variety of routes of novel suitably substituted .DELTA..sup.2,3 -1,4-morpholine-2-carboxylic acids possessing a fused .beta.-lactam ring in the 1,6-position and carrying a substituent cis to carbon 5 in the 7-position of the fused ring system represented by the general formula ##STR1## wherein Z is hydrogen or the residue of an ester group and X is acylamino. Also included in the invention are compounds of the above formula in which the carboxyl group at the 2-position is protected as by an easily cleavable ester group and salts of both the free acids and carboxyl-protected compounds. The compounds are potent antibacterial agents.

Abstract: There is described the stereoselective total synthesis by a variety of routes of novel suitably substituted .DELTA..sup.2,3 -1,4-morpholine-2-carboxylic acids possessing a fused .beta.-lactam ring in the 1,6-position and carrying a substituent cis to carbon 5 in the 7-position of the fused ring system represented by the general formula ##STR1## wherein Q is hydrogen, alkyl, aralkyl or --CH.sub.2 COOZ where Z is hydrogen or the residue of an ester group and X is amino, azido or acylamino. Also included in the invention are compounds of the above formula in which the carboxyl group at the 2-position is protected as by an easily cleavable ester group and salts of both the free acids and carboxyl-protected compounds. Those compounds in which X is acylamino and their physiologically hydrolyzed esters and pharmaceutically acceptable salts are potent antibacterial agents.

Abstract: There is described the stereoselective total synthesis by a variety of routes of novel suitably substituted .DELTA..sup.2,3 -1, 4-morpholine-2-carboxylic acids possessing a fused .alpha.-lactam ring in the 1,6-position and carrying a substituent cis to carbon 5 in the 7-position of the fused ring system represented by the general formula ##STR1## wherein Q is hydrogen, alkyl, aralkyl or -CH.sub.2 COOZ where Z is hydrogen or the residue of an ester group and X is amino, azido or acylamino. Also included in the invention are compounds of the above formula in which the carboxyl group at the 2-position is protected as by an easily cleavable ester group and salts of both the free acids and carboxyl-protected compounds. Those compounds in which X is acylamino and their physiologically hydrolyzed esters and pharmaceutically acceptable salts are potent antibacterial agents.

Abstract: There is described the stereoselective total synthesis by a variety of routes of novel suitably substituted .DELTA..sup.2,3 -1, 4-morpholine-2-carboxylic acids possessing a fused .beta.-lactam ring in the 1,6-position and carrying a substituent cis to carbon 5 in the 7-position of the fused ring system represented by the general formula ##STR1## wherein Q is hydrogen, alkyl, aralkyl or --CH.sub.2 COOZ where Z is hydrogen or the residue of an ester group and X is amino, azido or acylamino. Also included in the invention are compounds of the above formula in which the carboxyl group at the 2-position is protected as by an easily cleavable ester group and salts of both the free acids and carboxyl-protected compounds. Those compounds in which X is acylamino and their physiologically hydrolyzed esters and pharmaceutically acceptable salts are potent antibacterial agents.

Abstract: There is described novel substituted .DELTA..sup.2,3 -1, 4-morpholine-2-carboxylic acids possessing a fused .beta.-lactam ring in the 1,6-position and carrying a substituent cis to carbon 5 in the 7-position of the fused ring system represented by the general formula ##STR1## wherein Q is hydrogen or alkyl and X is amino. Also included in the invention are compounds of the above formula in which the carboxyl group at the 2-position is protected as by an easily cleavable ester group and salts of both the free acids and carboxyl-protected compounds. The compounds and their physiologically hydrolyzed esters and pharmaceutically acceptable salts are useful as intermediates in the preparation of antibacterial agents.