Isoxazole- and isothiazole-5-carboxamides

An isoxazole- or isothiazole- 5-carboxamide of the formula I ##STR22## where X is oxygen or sulfur;

• R.sup.1 is halogen,
• C.sub.1 -C.sub.4 -alkylaminocarbonyl, di-C.sub.1 -C.sub.3 -alkylaminocarbonyl or cyclopropylaminocarbonyl;
• R.sup.2 is COOR.sup.5, where
• R.sup.5 is hydrogen;
• C.sub.1 -C.sub.6 -alkyl which can carry 1 to 5 halogens and/or up to three hydroxyl and/or C.sub.1 -C.sub.4 -alkoxy groups;
• R.sup.3 is hydrogen or
• C.sub.1 -C.sub.6 -alkyl;
• R.sup.4 is hydrogen;
• C.sub.1 -C.sub.6 -alkyl which can carry one to three of the following:
• halogen, cyano, C.sub.1 -C.sub.4 -alkoxy, partially or completely halogenated C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -alkylthio, partially or completely halogenated C.sub.1 -C.sub.4 -alkylthio, di-C.sub.1 -C.sub.4 -alkylamino, C.sub.3 -C.sub.8 -cycloalkyl or phenyl, it being possible for the latter in turn to carry one to three of the following:
• halogen, cyano, nitro, C.sub.3 -C.sub.4 -alkyl, partially or completely halogenated C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, partially or completely halogenated C.sub.1 -C.sub.4 -alkoxy or C.sub.1 -C.sub.4 -alkylthio;
• C.sub.3 -C.sub.8 -cycloalkyl which can carry one to three of the following:
• halogen, nitro, cyano, C.sub.1 -C.sub.8 -alkyl, partially or completely halogenated C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.4 -alkoxy or partially or completely halogenated C.sub.1 -C.sub.4 -alkoxy;
• C.sub.3 -C.sub.6 -alkenyl or C.sub.3 -C.sub.6 -alkynyl, each of which can be substituted one to three times by halogen and/or once by phenyl which in turn can carry one to three of the following groups:
• C.sub.1 -C.sub.4 -alkyl;
• phenyl which can carry one to four of the following groups:
• C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -haloalkoxy, C.sub.1 -C.sub.4 -alkylthio, C.sub.1 -C.sub.4 -haloalkylthio, halogen, nitro, cyano, formyl, C.sub.2 -C.sub.4 -alkanyl, C.sub.2 -C.sub.4 -haloalkanoyl or C.sub.1 -C.sub.4 -alkoxycarbonyl;
• and the environmentally compatible salts of the compound I.