Design, synthesis, and insecticidal activities of novel meta-diamide compounds containing sulfide, sulfoxide and sulfone

In searching for novel insecticide lead, 21 new meta-diamide compounds containing sulfide, sulfoxide and sulfone were designed and synthesized regarding Cyproflanilide as leading compound. All the compounds were characterized by 1H NMR, 13C NMR and HRMS. The preliminary bioassay indicated that most of the title compounds exhibited excellent insecticidal activities against Nilaparvate lugens. Especially, the compound: N-(3-((2-bromo-6-(ethylthio)-4-(perfluoropropan-2-yl)phe-nyl)carbamoyl)-2-fluorophenyl)-N-(cyclopropylmethyl)nicotinamide (9d), exhibited 98.92 % mortality against N. lugens at 100 mg/L, better than cyproflanilide (0.00 % at 400 mg/L). Preliminary structure–activity relationship was also discussed based on insecticidal tests. This work helps in further exploitation of meta-diamide insecticide against hemipteran pests.