Abstract: New cephalosporins of the formula: ##STR1## in which n=0 or 1, R.sub.1 is a radical of the formula: ##STR2## [in which R.sub.4 is a protective radical and R.sub.5 is hydrogen, alkyl, vinyl, cyanomethyl or a protective radical], or R.sub.1 is a protective radical and R.sub.2 is a protective radical or an enzymatically removable radical, or R.sub.1 is an acyl radical which may be substituted in various ways and R.sub.2 is a protective radical, in the 3-oxoethyl-bicyclooct-2-ene or -bicyclooct-3-ene or 3-oxoethylidene-bicyclooctane form if n=0, and in the 3-oxoethyl-bicyclooct-2-ene or 3-oxoethylidene-bicyclooctane form if n=1, are useful as intermediates for the preparation of 3-thiovinyl-cephalosporins useful as antibacterial agents.

Abstract: New thiols of the general formula: ##STR1## wherein A represents a 2-hydroxy-1-oxoethan-1-yl-2-ylidene or alkoxycarbonylmethyne radical or a nitrogen atom and R represents various substituted alkyl radicals, and their alkali metal and alkaline earth metal salts are useful as intermediates in the preparation of cephalosporins having anti-bacterial properties.

Abstract: Novel 3-vinyl-cephalosporins of the formula ##STR1## in which n is 0 or 1, R.sub.1 is hydrogen, a radical of the formula ##STR2## [in which R.sub.4 is hydrogen or a protective radical and R.sub.5 is hydrogen, alkyl, vinyl or cyanomethyl or is a protective radical], or a protective radical, and R.sub.2 is hydrogen, a protective radical or an enzymatically removable radical, or R.sub.1 is hydrogen or an acyl radical which may carry various substituents and R.sub.2 is hydrogen or a protective radical, and R.sub.3 is a radical of the general formula R'.sub.3 --SO.sub.2 --O-- or R".sub.3 --CO--O--, in which R'.sub.3 is alkyl, trifluoromethyl, trichloromethyl or phenyl which is substituted by a halogen atom or by an alkyl or nitro radical, and R".sub.3 is defined like R'.sub.3 or represents methyl which is substituted by acyl or alkoxycarbonyl, or represents ethyl or propyl substituted in the 2-position by acyl or alkoxycarbonyl.

Abstract: Novel cephalosporins of the general formula (I); ##STR1## in which R is alkyl, L-2-amino-2-carboxy-ethyl, phenyl, pyridyl, pyridyl-N-oxide, pyrimidin-2-yl, substituted pyridazin-3-yl, 5,6-dioxo-1,4,5,6-tetrahydro-1,2,4-triazin-3-yl substituted in the 4-position, 1,3,4-triazol-5-yl or 2-alkoxycarbonyl-1,3,4-triazol-5-yl substituted in the 1-position, 1,4-dialkyl-5,6-dioxo-1,4,5,6-tetrahydro-1,2,4-triazin-3-yl, 1-alkyl-5,6-dioxo-1,4,5,6-tetrahydro-1,2,4-triazin-3-yl, 2-alkyl-5,6-dioxo-1,2,5,6-tetrahydro-1,2,4-triazin-3-yl, triazol-5-yl, 1,3,4-thiadiazol-5-yl which is substituted or unsubstituted, 1,2,4-thiadiazol-5-yl which is substituted, 1,3,4-oxadiazol-5-yl which is substituted or unsubstituted, oxazol-2-yl which is substituted or unsubstituted or tetrazol-5-yl which is substituted or unsubstituted in the 1-position, R' is a hydrogen atom or a radical of the general formula (II); ##STR2## and R.sup.o is hydrogen, alkyl, vinyl or cyanomethyl, as well as their salts, are useful as anti-bacterial agents.

Abstract: Novel 3-vinyl-cephalosporin derivates of the general formula ##STR1## in the bicyclooct-2-ene or bicyclooct-3-ene form, in which R.sub.1 is a protective radical or is a radical of the general formula ##STR2## in which R.sub.5 is hydrogen, alkyl, vinyl or cyanomethyl, or a protective radical, and R.sub.6 is hydrogen or a protective radical, and R.sub.2 is a protective radical or an enzymatically removable radical, or R.sub.1 is an acyl radical, which may carry various substituents, and R.sub.2 represents a protective radical, and R.sub.3 and R.sub.4, which are identical or different, represent alkyl (optionally substituted by hydroxyl, alkoxy, amino, alkylamino or dialkylamino) or phenyl, or form, together with the nitrogen atom, a saturated 5-membered or 6-membered heterocyclic ring optionally containing another hetero-atom, their E- and Z-forms and their mixtures, are useful as intermediates for the preparation of 3-thiovinyl cephalosporins useful as antibacterial agents.

Abstract: New thiazolo[3,2-c]-1,3-benzoxazine derivatives of the general formula (I), in which X is oxygen or sulfur, R.sub.1 and R.sub.2, which are identical or different, are hydrogen or halogen atoms or alkyl, alkoxy, alkylthio or trifluoromethyl radicals, in the 7-, 8-, 9- or 10-position, and R.sub.3 is a hydrogen atom or a carboxyl radical, their salts, if appropriate, their preparation and the medicaments in which they are present.These new derivatives are particularly useful as analgesic agents.

Abstract: .alpha.-Amino(1,3-dithiin-5-yl)-acetic acid in the D-, L-, or D,L-form and in which the amino radical is free or protected by tert.-butoxycarbonyl or 2,2,2-trichloroethoxycarbonyl is a useful intermediate in the preparation of cephalosporins having valuable antibacterial activity.

Abstract: The invention provides novel cephalosporins of the formula: ##STR1## in which R.sub.1 represents acetoxy, (5-methyl-1,3,4-thiadiazol-2-yl)-thio, (1-methyl-tetrazol-5-yl)-thio or [1-(2-hydroxyethyl)-tetrazol-5-yl]-thio and R.sub.2 represents carboxyl, or R.sub.1 represents pyridinio and R.sub.2 the carboxylato ion, and, when R.sub.2 represents carboxyl, their metal salts and addition salts with nitrogen-containing bases, which have useful antibacterial properties.

Abstract: New oxathiino- and dithiino-aminoacetic acids of the formula: ##STR1## in which A represents oxygen or sulphur, together with their racemic forms, their optically active forms and mixtures thereof, their reactive derivatives and their acid addition salts, are valuable intermediates for the preparation of therapeutically active derivatives, in particular cephalosporin derivatives of the formula: ##STR2## where R is hydrogen or acetoxy.

Abstract: New cephalosporin derivatives of the formula: ##STR1## in which either (a) R.sub.1 is hydrogen, acetoxy, azido or heterocyclylthio or heterocyclylcarbonylthio which is (1,3,4-thiadiazol-2-yl)-thio which is unsubstituted or substituted by straight or branched chain C.sub.1-4 alkyl or alkoxy, straight or branched chain C.sub.1-4 alkylthio, straight or branched chain C.sub.1-4 alkylsulphonyl, amino or acetylamino; (1,2,3,4-tetrazol-5-yl)-thio which is unsubstituted or substituted in the 1-position by straight or branched chain C.sub.1-4 alkyl, hydroxy straight or branched chain C.sub.1-4 alkyl, phenyl or hydroxyphenyl, or in the 2-position by straight or branched chain C.sub.1-4 alkyl or hydroxy straight or branched chain C.sub.1-4 alkyl; (1,2,4-triazol-3-yl)-thio, (4-methyl-1,3-thiazol-2-yl)-thio, (3-methyl-1,2,4-thiadiazol-5-yl)-thio or (1,2,3-thiadiazol-4-yl)-carbonylthio, and R.sub.

Abstract: New cephalosporin derivatives of the general formula: ##STR1## in which R represents a straight or branched chain C.sub.1-4 alkyl radical, or a phenyl (straight or branched chain C.sub.1-4 alkyl) radical, n is 0, 1 or 2, and either R.sub.1 is a pyridinio ion and R.sub.2 is a carboxylato ion, or R.sub.1 represents a hydrogen atom, or an acetoxy, (5-methyl-1,3,4-thiadiazol-2-yl)-thio or (1-methyl-1,2,3,4-tetrazol-5-yl)-thio radical and R.sub.2 represents a carboxy radical or a radical of the formula; ##STR2## in which the radical: ##STR3## is a radical which can be removed easily by enzymatic means and in which R.sub.3 represents a hydrogen atom or a straight or branched chain C.sub.1-4 alkyl radical, a phenyl radical or a phenyl (C.sub.1-2 alkyl) radical and R.sub.4 represents a straight or branched chain C.sub.1-4 alkyl radical, a straight or branched chain C.sub.1-4 alkoxy radical, a cyclohexyl radical, a phenyl radical or a phenyl (C.sub.

Abstract: New cephalosporin compounds of the formula: ##STR1## in which A is oxygen or sulphur, R.sub.1 is hydrogen or acetoxy and R.sub.2 is carboxy or a radical of the formula: ##STR2## in which the radical ##STR3## is a radical which can be easily removed enzymatically, and in which R.sub.3 is hydrogen or straight or branched chain C.sub.1-4 alkyl and R.sub.4 is straight or branched chain C.sub.1-4, alkyl or cyclohexyl, together with its diastereoisomeric forms and mixtures thereof, its acid addition salts and, where appropriate, its pharmaceutically acceptable non-toxic metal salts and addition salts with nitrogen-containing bases other than ammonia, exhibit valuable anti-bacterial properties, in particular against Gram-positive and Gram-negative bacteria.

Abstract: New cephalosporin derivatives of the formula: ##STR1## wherein one of A and A.sub.1 represents oxygen or sulphur and the other represents sulphur, R.sub.1 represents hydrogen, acetoxy, (5-methyl-1,3,4-thiadiazol-2-yl)thio or (1-methyl-1,2,3,4-tetrazol-5-yl)thio and R.sub.2 represents carboxy, or R.sub.1 represents a pyridinio radical and R.sub.2 represents the carboxylate ion, are therapeutically useful compounds possessing antibacterial properties.