DK341474

The novel anthelmintically active 2-carbalkoxy-amino-benzimidazole-5(6)-phenyl ethers and thioethers of the formula I wherein R1 denotes alkyl having 1 to 4 carbon atoms, R2 and R3 independently of one another each denote hydrogen, hydroxyl, alkoxy having 1 to 4 carbon atoms, halogen, trifluoromethyl, alkyl having 1 to 4 carbon atoms or carbalkoxy having 1 to 4 carbon atoms in the alkoxy radical, R4 denotes hydrogen or chlorine and X denotes oxygen of sulphur, are prepared by reaction of appropriately substituted o-phenylenediamine derivatives with an appropriately substituted dithiomethyleneamino-formic acid ester. The compounds are valuable chemotherapeutics for the control of parasitic diseases in man and animals. They are particularly active against a large number of helminths, for example Haemonchus, Trichostrongylus, Ostertagia, Strongyloides, Cooperia, Chabertia, Oesophagostomum, Hyostrongylus, Ankylostoma, Askaris and Heterakis.