Abstract: Oxazole and isoxazole derivatives of the formula ##STR1## wherein A is C.sub.1-6 -alkylene, Het is a 2-R-oxazol-5-yl, 5-R-oxazol-2-yl, 4-R-oxazol-2-yl, 2-R-oxazol-4-yl, 3-R-isoxazol-5-yl or 5-R-isoxazol-3-yl group which is optionally substituted on the heterocyclic ring by a C.sub.1-6 -alkyl group, R is phenyl or thienyl monosubstituted or disubstituted by halogen, trifluoromethyl or C.sub.1-6 -alkylthio, R.sup.1 and R.sup.2 each is a C.sub.1-6 -alkyl group and R.sup.3 is a hydroxy or C.sub.1-6 -alkoxy group or a group of the formula --NR.sup.4 R.sup.5 in which R.sup.4 and R.sup.5 each is a hydrogen atom or a C.sub.1-6 -alkyl group or R.sup.4 and R.sup.5 together with the nitrogen atom to which they are attached is a 5-membered or 6-membered saturated heteromonocyclic ring which may contain an oxygen or sulphur atom or an additional nitrogen atom, and pharmaceutically acceptable salts of the compounds of formula I in which R.sup.3 is a hydroxy group with bases, have anti-arthritic activity.

Abstract: Nitroimidazoles of the formula ##STR1## wherein R.sup.1 and R.sup.2 are as hereinafter set forth, are described. The nitroimidazoles are useful as hypoxic-cell radiosensitizers, as well as being useful as antiprotozoal agents.

Abstract: This invention is directed toward pharmacologically active compounds of the formula ##STR1## wherein A represents a nitrogen atom which may be substituted by a methyl, cyclopropylmethyl, di(C.sub.1-4 alkyl)aminoethyl, methoxymethyl or hydroxyethyl group and B represents a carbonyl group or A and B together represent a grouping of the formula ##STR2## in which R.sup.a represents a hydrogen atom or a lower alkyl or hydroxymethyl group and X represents a nitrogen atom or C--R.sup.b wherein R.sup.b represents a hydrogen atom or a lower alkyl or hydroxymethyl group; R represents a halogen atom or a nitro or trifluoromethyl group; R.sup.1 represents a hydrogen atom or a lower alkyl group; R.sup.2 represents an acyl group derived from a naturally occurring amino acid (all such groups which contain an asymmetric carbon atom having the L- or D,L-configuration) and R.sup.3 represents a phenyl, halophenyl or 2-pyridyl group and acid addition salts thereof.

Abstract: This invention is directed toward pharmacologically active compounds of the formula ##STR1## wherein A represents a nitrogen atom which may be substituted by a methyl, cyclopropylmethyl, di(C.sub.1-4 alkyl)aminoethyl, methoxymethyl or hydroxyethyl group and B represents a carbonyl group or A and B together represent a grouping of the formula ##STR2## in which R.sup.a represents a hydrogen or a lower alkyl or hydroxymethyl group and X represents a nitrogen atom or C-R.sup.b wherein R.sup.b represents a hydrogen atom or a lower alkyl or hydroxymethyl group; R represents a halogen atom or a nitro or trifluoromethyl group; R.sup.1 represents a hydrogen atom or a lower alkyl group; R.sup.2 represents an acyl group derived from a naturally occurring amino acid (all such groups which contain an asymmetric carbon atom having the L- or D,L-configuration) and R.sup.3 represents a phenyl, halophenyl or 2-pyridyl group and acid addition salts thereof.