Substituted 1,2,4-oxadiazole derivatives of the formula (I) and their stereoisomers ##STR1## in which formula R.sup.1 represents hydrogen, C.sub.1-8 -alkyl which is optionally substituted by halogen, cycloalkyl, alkoxy, hydroxyl, aryl, alkylcarbonyl, alkoxycarbonyl and cycloalkyl, and their use as endoparasiticides.
公式(I)及其立体异构体的取代1,2,4-噁二唑衍
生物##STR1##其中公式中R.sup.1代表氢,C.sub.1-8 -烷基,该烷基可以选择性地被卤素取代,环烷基,烷氧基,羟基,芳基,烷基羰基,烷氧羰基和环烷基,并将它们用作内寄生虫药物。