New Fungicidally Active Pyrazolyl-Substituted 1,3,4-Thiadiazole Compounds and Their Preparation

摘要

The potassium dithiocarbazate 2 was obtained through condensation of 5-pyrazolehydrazide 1 with carbon disulfide in ethanolic potassium hydroxide, and its cyclization gave 5pyrazolyl-1.3,4-thiadiazole-2-th 3 in concentrated sultliric acid. Alkylation of 3 yielded 2alkylthio-5-pyrazolyl-1,3.4-thiadiazole 4. The preliminary bioassay tests indicated that compounds3 and 4 have fungicidal activity.