Synthesis and fungicidal activity of fluorine-containing chlorothalonil derivatives

摘要: Abstract Fourteen new fluorine-containing chlorothalonil derivatives were synthesized by using intermediate derivatization method (IDM) in order to discover novel antifungal compounds for controlling corn rust. The structures of confirmed 1H NMR, 13C 19F elemental analysis, HRMS and X-ray. bioassay results indicated that compound 2,4,5-trichloro-6-(2,6-dichloro-4-[trifluoromethyl]phenylamino)isophthalonitrile (3j, Rn is 2,6-Cl2-4-CF3) had the optimal structure with best fungicidal activity against rust (98%, 70% controls) at 25 6.25 mg/L concentration, respectively, much better than fluazinam, highlighting importance trifluoromethyl group on 4-position benzene ring. structure–activity relationship was discussed as well.