Design, synthesis and structure-activity relationship of novel diphenylamine derivatives

Article abstract of DOI:10.1016/j.bmc.2015.09.032

Diphenylamine derivatives have been reported with good fungicidal, insecticidal, acaricidal, rodenticidal and/or herbicidal activities. To find new lead compound of this kind, a series of novel diphenylamine derivatives were designed and synthesized by the approach of Intermediate Derivatization Methods. All compounds were identified by ¹H NMR and elemental analysis. Bioassays demonstrated that some compounds substituted at 2,4,6-positions or 2,4,5-positions of phenyl ring B exhibited excellent fungicidal activities. The optimal compounds P30 and P33 showed 80% and 85% control respectively against cucumber downy mildew at 12.5 mg L^-1, both 100% control against rice blast at 0.3 mg L^-1 and both 100% control against cucumber gray mold at 0.9 mg L^-1. The relationship between structure and fungicidal activities was discussed as well.