| abstract |
A method of combating parasitic protozoa which comprises applying thereto an amount effective therefor of a 1,2,4-triazinedione of the formula <IMAGE> I in which R1 represents optionally substituted pyridyl, pyrazinyl or pyrimidinyl, X represents O, S, SO, SO2 or -CR4(CN)-, R2 represents hydrogen, one or more, identical or different radicals of the group comprising hydrogen, halogen, nitro, alkyl, alkoxy, alkylthio, halogenoalkyl, halogenoalkoxy, alkylthio and halogenoalkylthio, R3 represents hydrogen, optionally substituted alkyl, alkenyl, alkinyl or aralkyl, and R4 represents hydrogen or alkyl. |