Synthesis and Fungicidal Activities of Novel 1,2,4-Triazole Thione Derivatives Containing 1,2,3-Triazole and Substituted Piperazine Moieties

A series of novel 1,2,4-triazole thione derivatives containing 1,2,3-triazole and substituted piperazine moieties were synthesized via the Mannich reaction of 1,2,3-triazole-containing 1,2,4-triazole thiol intermediates with various substituted piperazines and formaldehyde in high yields. The structures of 14 title compounds were confirmed by melting points, IR, ¹H NMR, ¹³C NMR, and elemental analysis. The bioassay results showed that some of the title compounds exhibit significant fungicidal activities against several plant fungi at 50 μg/mL, especially trifluoromethyl-containing triazole thione derivative 9g showed broad activities and could be made further structural optimization for novel fungicides innovation research.