Synthesis, Structure Characterization and Fungicidal Activity of 1,3-Disubstituted-1h-1,2,4-triazole-5-amines

A novel series of 1,3-disubstituted-1H-1,2,4-triazole-5-amines were synthesized via hydrazinolysis, condensation, alkylation and acid-catalyzed intramolecular cyclization starting from nitroguanidine 1. Their structures were characterized by IR, H-1 NMR, C-13 NMR and HRMS analysis. The preliminary bioassay indicated that most of them showed certain extent of growth inhibition in vitro against six phytopathogen fungi. Compared with other target compounds, 1-(n-butyl)-3-(4-chlorophenyl)-1H-1,2,4-triazole-5-amine (6y) was found to have high activity and the widest fungicidal spectrum. Its inhibition rates to five pathogens were all above 53%. This kind of compounds could be synthesized and derived easily, and were valuable as lead structure for future developing novel fungicides.