Abstract: A compound of formula I ##STR1## with R.sup.1 being an alkyl group substituted by one or more substituents and esters thereof at the 2-carboxy group or at the 8-hydroxy group or both; and salts thereof. Compounds I have antibacterial effect. Various intermediates are described. This compound of the formula I, or an ester at the 2-carboxy group or at the 8-hydroxy group or both or a salt thereof is produced by reacting a compound of formula II or of formula IX ##STR2## in which R represents a hydrogen atom or a carboxy protecting group, R.sup.3 represents an activated carboxylic acid group, R.sup.4 represents an alkyl group having 1 to 4 carbon atoms, or a phenyl group which may be unsubstituted or substituted, R.sup.15 represents a phenyl group or an alkyl group having from 1 to 4 carbon atoms, and X represents an oxygen or sulphur with an amine of the formula III R.sup.1 NH.sub.

Abstract: A compound of the formula I ##STR1## in which R.sup.1 represents a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms, the --CONHR.sup.1 group being present at the 3- or 4-position on the phenyl ring, and esters thereof at the 2-carboxyl group and/or at the 8-hydroxy group, have antibacterial and/or .beta.-lactamase inhibiting activity.

Abstract: Intermediate compounds of the formula ##STR1## for the preparation of antibacterially active penem compounds and salts wherein R is hydrogen or an esterifying group, R.sup.1 is an unsubstituted or a mono-, di-, or tri-substituted phenyl, naphthyl, thienyl, pyridyl, quinolyl or isoquinolyl, R.sup.2 is hydrogen or a hydroxyl group which may be protected, R.sup.4 is chlorine or bromine and R.sup.5 is an alkyl or phenyl group; methods for making such compounds or salts.

Abstract: The present invention relates to certain penem derivatives of the general formula I ##STR1## in which R represents a hydrogen atom or a carboxyl esterifying group, R.sup.1 represents certain unsubstituted and substituted aromatic and heterocyclic groups, and R.sup.2 represents a hydrogen atom, an unsubstituted or substituted alkyl or aryl group.The compound of formula I and salts thereof may be used in the treatment of bacterial infections in man and other animals.

Abstract: Penem-derivatives of the formula I ##STR1## in which R is hydrogen or a carboxyl esterifying groupR.sup.1 is phenyl, naphthyl, thienyl, pyridyl, quinolyl or isoquinolyl any of which is optionally substituted by one, two or three substituents of the group halogen, cycloalkyl, --NH.sub.2, --CONH.sub.2, --NO.sub.2, --CN, --R.sup.2, --OR.sup.2, --SR.sup.2, --SO--R.sup.2, --SO.sub.2 R.sup.2, --CO--R.sup.2, --CO--O--R.sup.2, --CH.sub.2 --CO--O--R.sup.2, --NHR.sup.2, --NR.sup.2 R.sup.2', --CO--NH--R.sup.2, --CO--NR.sup.2 R.sup.2', --NH--CO--R.sup.2, --NH--CO--NH--R.sub.2, --NH--CO--NH--R.sup.2, --NH--SO.sub.2 --R.sup.2, --CF.sub.3, --CO--OH, --CO.sub.2 --CO--OH wherein R.sup.2 and R.sup.2' are the same or different and each represents alkyl of 1 to 4 carbon atomsor a salts thereof, process for the manufacture thereof and antibacterial pharmaceutical preparations containing them.

Abstract: Antibacterially active penem compounds and salts of the formula ##STR1## wherein R is hydrogen or an esterifying group, R.sup.2 is hydrogen, hydroxy, or protected hydroxy, and R.sup.1 is phenyl, naphthyl, thienyl, pyridyl, quinolyl, or isoquinolyl, or such a group which is mono-, di-, or tri-substituted; methods for making such compounds or salts; and antibacterial pharmaceutical preparations containing the compounds or salts.