Synthesis and Antifungal Evaluation of Novel 1,2,4‐oxadiazole Derivatives with Cyclic Amine Moiety

Abstract To discover new and highly effective fungicides, 17 novel 1,2,4‐oxadiazole derivatives with cyclic amine moiety were designed and synthesized. Their structures were characterized by 1 H NMR, 13 C NMR, and HRMS. Preliminary bioassay data indicated that some of the target compounds showed excellent antifungal activity against soybean rust. Especially, compounds 4d , 4h , and 4j showed more than 50% inhibitory activity against soybean rust at 4 mg L −1 , better than flufenoxadiazam 30% at 4 mg L −1 . Studies show that novel 1,2,4‐oxdiazole derivatives with cyclic amine moiety provide some clues for the development of new fungicides.