3-alkyl-4-amino-5-mercapto-1,2,4-triazoles (1) as the starting material were condensed with 2,4- dichlorophenoxyacetic acid or β-naphthoxyacetic acid in the presence of phosphorus oxychloride and twelve novel compounds of 3- alkyl- 6- (2,4- dichloro- phenoxymethylene) -S- triazolo [3,4,-b]-1,3,4- thiadiazoles 2a～ e and 3- alkyl-6-β- naphthoxymethylene-S-triazolo [3,4,-b]-1,3,4- thiadiazoles 3f～k were obtained. The structures of these compounds were distinguished by elemental analysis, IR, ^1H NMR and MS. Preliminary experiments in bioassay showed that some of these produts have herbicidal and fungical activities.

Key words: BIOLOGICAL ACTIVITY