Abstract: An isoxazole compound having the following formula: ##STR1## wherein R.sup.1 represents hydrogen, halogen, alkyl, alkoxy, hydroxyl, alkylthio, amino, alkanoyl, alkanoylamino, alkanoyloxy, alkoxycarbonyl, carboxy, (alkylthio)thiocarbonyl, carbamoyl, nitro or cyano; R.sup.2 represents an amino; m is 2 or 3; n is 1 to 6; ring A represents a phenyl ring, a naphthyl ring or an aromatic heterocycle; and X represents oxygen or sulfur. The isoxazole compound has an excellent monoamine oxidase inhibitory activity, and is useful for treating Parkinson's disease, depression and Alzheimer's disease.

Abstract: Isoxazole compounds having the following general formula: ##STR1## wherein R.sup.1 represents an optionally substituted aryl group or aromatic heterocyclic group; R.sup.2 represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, an alkoxy group, a cyano group, a carboxyl group, an alkanoyl group, an alkoxycarbonyl group or an optionally substituted carbamoyl group; R.sup.3 represents an optionally substituted amino group or a saturated heterocyclic group; X represents an oxygen atom or a sulfur atom; and n is an integer of from 2 to 6. These compounds have excellent monoamine oxidase inhibitory activity and are useful as a therapeutic agent or a preventive agent against nervous diseases such as depression.

Abstract: An isoxazole compound having the following formula: wherein R.sup.1 represents hydrogen, halogen, alkyl, alkoxy, hydroxyl, alkylthio, amino, alkanoyl, alkanoylamino, alkanoyloxy, alkoxycarbonyl, carboxy, (alkylthio)thiocarbonyl, carbamoyl, nitro or cyano; R.sup.2 represents an amino; m is 1; n is 1 to 6; ring A represents a phenyl ring or a naphthyl ring; and X represents oxygen or sulfur. The isoxazole compound has an excellent monoamine oxidase inhibitory activity, and is useful for treating Parkinson's disease, depression and Alzheimer's disease.

Abstract: Compounds of formula (I): ##STR1## wherein R.sup.1 is hydrogen, halogen or alkyl; R.sup.2 is hydrogen, alkyl, optionally substituted phenyl or a heterocycle; or R.sup.1 and R.sup.2 together form a group of formula --CR.sup.4 .dbd.CR.sup.5 --CR.sup.6 .dbd.CR.sup.7 --, where R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are hydrogen, halogen, alkyl group, alkoxy, halomethyl, alkylamino, dialkylamino, hydroxy, nitro, aliphatic carboxylic acylamino or amino; and R.sup.3 is piperidyl, substituted piperidyl or quinuclidinyl. The compounds are useful in the treatment and prophylaxis of cognitive disorders, notably senile dementia, including Alzheimer's disease. Processes for preparing the compounds are also provided.

Abstract: Compounds of formula (I): ##STR1## [in which: either (a) the dotted line ( ) is a single bond; A=is oxygen; and B is a group of formula (II): ##STR2## (in which m is 0 and n is 0 or 1) or (b) the dotted line ( ) is a double bond; A=is said group of formula (II) in which m is 1 and n is 0 or 1; and B is absent; and R.sup.1 is hydrogen, halogen, alkyl, alkenyl, alkynyl, optionally substituted benzyl or optionally substituted phenyl; R.sup.2 is hydrogen, halogen, alkyl, optionally substituted phenyl or heterocyclic; or R.sup.1 and R.sup.2, together with the carbon atoms to which they are attached, are a hydrocarbon ring fused to the isoxazole ring; R.sup.3 and R.sup.4 are each hydrogen, alkyl, optionally substituted benzyl or optionally substituted phenyl; or R.sup.3, R.sup.4 and the nitrogen atom to which they are attached together represent an alicyclic amino group]; and salts thereof may be used for the treatment of cerebral circulatory problems and for use as centrally acting muscle relaxants.