Abstract: Quinolinecarboxylic acid derivatives of the formula (I) ##STR1## and pharmaceutically acceptable salts thereof, wherein R.sup.1 is hydrogen, straight or branch chain lower alkyl or phenyl unsubstituted or substituted by one or more halo moieties; R.sup.2 is hydrogen or straight or branch chain lower alkyl; and R.sup.3 is hydrogen, halo or straight or branch chain lower alkoxy, are useful for treating bacterial infections in humans and animals.

Abstract: Compounds of the formula ##STR1## and pharmaceutically acceptable salts thereof, R.sup.1 is hydrogen, alkyl or aryl unsubstituted or substituted by one or two halo moieties, R.sup.3 is hydrogen or alkyl, A is N, W is O or NR.sup.3 wherein R.sup.3 is hydrogen, alkyl, acyl, haloacyl, 2alkoxycarbonyl or (5-methyl-2-oxo-1,3-dioxolen-4-yl) methyl are useful for treating bacterial infections in humans and animals.

Abstract: Quinolinecarboxylic acid derivatives of the formula (I) ##STR1## and pharmaceutically acceptable salts thereof wherein R.sup.1 is hydrogen, straight or branch chain lower alkyl or phenyl unsubstituted or substituted by one or more halo moieties; R.sup.2 is hydrogen or straight or branch chain lower alkyl; and ##STR2## is a 5- or 6-membered ring wherein the nitrogen atom is the only heteroatom or where there is a second heteroatom selected from the group consisting of nitrogen, oxygen and sulfur, said 5- or 6-membered ring being unsubstituted or substituted by lower alkyl, amino or mono- or di-lower alkyl amino are useful for treating bacterial infections in humans and animals.

Abstract: Compounds of the formula ##STR1## and pharmaceutically acceptable salts thereof, R.sup.1 is hydrogen, alkyl or phenyl unsubstituted or substituted by one or two halo moieties, R.sup.2 is hydrogen or alkyl, A CX wherein X is halo, B is O or NR.sup.3 wherein R.sup.3 is hydrogen, alkyl, acyl, haloacyl, 2alkoxycarbonyl or (5-methyl-2-oxo-1,3-dioxolen-4-yl) methyl are useful for treating bacterial infections in humans and animals.

Abstract: Anti-bacterial and anti-fungal compounds of formula I and pharmaceutically acceptable salts thereof: ##STR1## in which R.sup.1 is hydrogen, alkyl or substituted or unsubstituted phenyl; R.sup.2 is hydrogen, alkyl, alkoxy, hydroxy, halgen, nitro or substituted or unsubstituted amino; R.sup.3 is hydrogen or substituted or unsubstituted alkyl; R.sup.4 and R.sup.5 are the same or different and are alkyl or hydroxyalkyl or R.sup.4 and R.sup.5 together with the nitrogen atom to which they are attached form an unsubstituted or substituted heterocyclic ring having the depicted nitrogen atom as the sole heteroatom or which may have nitrogen, oxygen or sulphur atoms as additional heteroatoms; and X is halogen.

Abstract: Quinolinecarboxylic acid derivatives, such as compound 7-fluoro-8-(4-methyl-1-piperazinyl)-5-oxo-1,2-dihydro-5H-thiazolo(3,2-a)-q uinoline-4-carboxylic acid, a pharmaceutical composition containing the same and methods of treatment of bacterial and fungal infections using the same.