In order to find new lead compounds with high pesticidal activity, a series of 1,3,4-oxadiazole thioether compounds (5 series) were designed by using penthiopyrad as a synthon. They were synthesized easily via five steps by using ethyl 4,4,4-trifluoro-3-oxobutanoate and triethyl orthoformate as starting materials. The synthesized compounds were characterized by ¹H NMR, ¹³C NMR and HRMS. The compound 2-(benzylthio)-5-(1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-1,3,4-oxadiazole (5a) was further determined by X-ray single-crystal diffraction. It crystallized in the monoclinic system, space group P2₁/c, Z = 4. All the 1,3,4-oxadiazole thioether derivatives were screened for fungicidal activity against ten fungi and herbicidal activity against two weeds. The bioassay results indicated that some of the synthesized 1,3,4-oxadiazole compounds exhibited good fungicidal activity (> 50% inhibition) against the plant pathogens Sclerotinia sclerotiorum and Rhizoctonia solani at 50 μg/mL. Some of them exhibited certain herbicidal activity, and compounds 2-((3-chlorobenzyl)thio)-5-(1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-1,3,4-oxadiazole (5e) and 2-((4-bromobenzyl)thio)-5-(1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-1,3,4-oxadiazole (5 g) had bleach effect. Molecular docking is to find the best fit orientation of the 2-((4-bromobenzyl)thio)-5-(1-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-1,3,4-oxadiazole (5 g) molecule with the SDH protein (PDB: 2FBW). The docking results indicate that the compound 5 g and the lead compound penthiopyrad have similar binding interactions with SDH and carbonyl is a key group for these compounds.

为了寻找具有高农药活性的新先导化合物，以吡噻菌胺为合成子，设计了一系列1,3,4-恶二唑硫醚化合物（ 5系）。以 4,4,4-三氟-3-氧代丁酸乙酯和原甲酸三乙酯为起始原料，通过五个步骤轻松合成它们。合成的化合物通过¹ H NMR、¹³ C NMR和HRMS进行表征。化合物2-(苄硫基)-5-(1-甲基-3-(三氟甲基) -1H-吡唑-4-基)-1,3,4-恶二唑( 5a )通过X射线单-晶体衍射。它在单斜晶系中结晶，空间群P2 ₁ /c , Z = 4.筛选所有1,3,4-恶二唑硫醚衍生物对十种真菌的杀真菌活性和对两种杂草的除草活性。生物测定结果表明，一些合成的 1,3,4-恶二唑化合物在 50 μg/mL 时对植物病原菌核盘菌和立枯丝核菌表现出良好的杀菌活性（> 50% 抑制）。其中一些表现出一定的除草活性，化合物2-((3-氯苄基)硫基)-5-(1-甲基-3-(三氟甲基)-1 H-吡唑-4-基)-1,3,4-恶二唑 ( 5e)和 2-((4-溴苄基)硫代)-5-(1-甲基-3-(三氟甲基)-1 H-吡唑-4-基)-1,3,4-恶二唑(5 g)有漂白作用。分子对接是寻找2-((4-溴苄基)硫代)-5-(1-甲基-3-(三氟甲基)-1 H-吡唑-4-基)-1,3,4的最佳拟合方向-恶二唑(5 g)分子与 SDH 蛋白 (PDB: 2FBW)。对接结果表明化合物5g和先导化合物吡噻菌胺与SDH具有相似的结合相互作用，羰基是这些化合物的关键基团。