Use of substituted 2-mercapto-nicotinic acid derivatives for combat against endoparasites, novel substituted 2-mercaptonicotinir acid derivatives and processes for their preparation

摘要

The present invention relates to the use of compounds of the general formula I IMAGE in which R1 represents C1-C8 alkyl, aralkyl, aryl or heteroaryl radicals which are optionally substituted by halogen, cyano, nitro, amino, alkylamino, aminoacyl, alkyl, aralkyl, haloalkyl, alkoxy, aryloxy, haloalkoxy, alkylthio, arylthio, alkylsulphinyl, arylsulphinyl, arylsulphonyl, haloalkylthio, haloalkylsulphinyl, haloalkylsulphonyl or carbonylaryl, X represents O or N-R3, R2 represents C1-5-alkyl, aralkyl, alkenyl or alkynyl, R3 represents H or alkyl or R1 and R3, together with the adjacent N atom, represent a 5- or 6-membered heterocycle which can contain O or N as further heteroatoms and is optionally substituted by C1-4-alkyl, R4 represents hydrogen, halogen, alkyl, haloalkyl, cyano, nitro, amino, aminoacyl, phenyl, alkoxy, thioalkyl, aryloxy or arylthio, each of which is optionally substituted, for combating endoparasites, to novel compounds of the formula I and to their preparation.