Indazole-3-carboxylic acid derivatives

Abstract

An indazole-3-carboxylic acid derivative represented by the following general formula (I) or its physiologically acceptable acid addition salt or quaternary ammonium salt, ##STR1## wherein Y represents --NH-- or --O--; R.sub.1 and R.sub.2 are identical or different and each represents a hydrogen atom, a lower alkyl group, a substituted lower alkyl group, a cycloalkyl group, a lower alkenyl group, a cycloalkenyl group, a lower alkynyl group, an unsubstituted or substituted aryl-lower alkyl group, a lower alkoxycarbonyl group, an unsubstituted or substituted aralkyloxycarbonyl group or an acyl group, or R.sub.1 and R.sub.2, taken together, form a lower alkylene group; R.sub.3 represents a hydrogen atom, a lower alkyl group, or a phenyl group; R.sub.4 represents a hydrogen atom, a lower alkyl group, a substituted lower alkyl group, a cycloalkyl group, a lower alkenyl group, a cycloalkenyl group, a lower alkynyl group, an unsubstituted or substituted aryl-lower alkyl group, a lower alkoxycarbonyl group, an unsubstituted or substituted aralkyloxycarbonyl group or an acyl group; R.sub.5 represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a hydroxyl group, a trifluoromethyl group, a nitro group, an amino group or an acylamino group; m represents a number of 1, 2, 3 or 4; n represents a number of 1, 2 or 3; and p represents a number of 1, 2, 3 or 4. This compound is useful as a potent and selective antagonist of serotonin 3 (5--HT.sub.3) receptor.