Abstract:

In order to find active pesticide leading compounds, thinking about that triazolothiadiazoles had various biological activities, this paper designed and synthesized 11 novel title compounds from 3-substituted-4-amino-5-mercapto-1,2,4-triazoles with heterocyclic carboxylic acid via cyclization in the presence of phosphoryl chloride by the princple of combination of active strucural moieties. The structures of the title compounds were characterized by melting point, IR, 1HNMR and elemental analysis. The results of bioassay experiments with 10 commonly used fungi showed that, all the title compounds had satisfactory fungicidal activity against Botrytis cinerea, the growth inhibition rate of compounds 5ae, 5ag, 5bd against Botrytis cinerea were up to 70% and for 5ad, 5cd, 5ce were more than 60%; compound 5bd exhibited fungicidal activity against Pellicularia sasakii with growth inhibition up to 60%, the growth inhibition rate of compound 5cg against Colletotrichum lagenarium was 69%.

Key words: triazolo[3,4-b]thiadiazole, synthesis, fungicide