Synthesis and antifungal activity of novel sulfone derivatives containing 1,3,4-oxadiazole moieties.

A series of new sulfone compounds containing 1,3,4-oxadiazole moieties were synthesized. The structures of these compounds were confirmed by spectroscopic data (IR, ¹H- and ¹³C-NMR) and elemental analyses. Antifungal tests indicated that all the title compounds exhibited good antifungal activities against eight kinds of plant pathogenic fungi, and some showed superiority over the commercial fungicide hymexazol. Among them, compounds 5d, 5e, 5f, and 5i showed prominent activity against B. cinerea, with determined EC₅₀ values of 5.21 μg/mL, 8.25 µg/mL, 8.03 µg/mL, and 21.00 µg/mL, respectively. The present work demonstrates that sulfone derivatives such as 5d containing a 1,3,4-oxadiazole moiety can be used as possible lead compounds for the development of potential agrochemicals.