Abstract: 7.beta.- 2-(aminothiazolyl and thiadiazolyl)-2-oxyiminoacetamido!cephalosporin derivatives having a 3- N-(optionally substituted) aminopyridiniumthiomethyl! substituent have antibacterial activity and are of use in antibacterial therapy. Processes for the preparation of such cephalosporins plus intermediates for use in the preparation thereof, including N-(optionally substituted)amino-thiopyridones, are also described.

Abstract: 7 .alpha.-formamido cephalosporin derivatives having a 3[N-(optionally substituted)aminothiopyridinium thiomethyl] substituent have anti-bacterial activity and are of use in anti-bacterial therapy. Processes for the preparation thereof and intermediates for use in these processes are also disclosed.

Abstract: Compounds of the formula (II): ##STR1## wherein X is halogen, hydroxyl or functionalized hydroxyl; Y is halogen, hydroxyl or alkoxy; R.sup.1 is a carboxylic acid group and ester thereof and amide derivative thereof or cyano; and R.sup.2 is hydrogen, a hydrocarbon, a heterocycle, a carboxylic acid group, a carboxylic acid ester, a carboxylic acid amide derivative, acyl, cyano, isocyano or an optionally substituted imine of the formula --CH.dbd.NZ or --N.dbd.CH.sub.2 wherein Z is hydrogen, alkyl, aryl, sulphonyl, --SR.sup.a, sulphoxide --SR.sup.a, or sulphonate --SR.sup.a wherein R.sup.a is alkyl of 1 to 6 carbon atoms or aryl, are useful as intermediates for the ultimate production of penicillins or cephalosporins.

Abstract: A process for the preparation of 3-substituted thiophenes which involves cyclization of a novel intermediate, avoids the use of previously employed expensive starting materials. The thiophenes are useful for the preparation of penicillins and cephalosporins.The process is for the preparation of a thiophene of formula (I): ##STR1## where R.sup.1 represents a carboxylic acid group, or an ester or amide thereof or a nitrile group; R.sup.2 represents a group suitable for use as an .alpha.-substituent in the side-chain of a penicillin or cephalosporin; which comprises treating a compound of formula (II): ##STR2## wherein X represents halogen or optionally functionalized hydroxyl, Y represents halogen, hydroxyl, or alkoxy; with a source of nucleophilic sulphur under basic conditions.