Synthesis and Anti-insect Activity of Triazole-Containing Amide Derivatives

The outbreak of crop diseases and insect pests, especially hemipteran piercing insects, poses a major threat to global food security. This study was designed to synthesize a series of novel flonicamid (FL) derivatives using an active substructure splicing strategy. Their insecticidal activities were evaluated against key pests, including Myzus persicae, Bemisia tabaci and Tetranychus urticae. The LC50 values of compounds 3ea, 3fa, 3ga, and 5cab against B. tabaci were 69.8 mg/L, 186 mg/L, 91.9 mg/L, and 112 mg/L, respectively. For M. persicae, the LC50 values of compounds 3aa, 5gaa, and 5fab were 5.31 mg/L, 5.43 mg/L, and 4.67 mg/L, respectively, with compound 5fab exhibiting significantly better activity than the reference FL (5.08 mg/L). Molecular docking revealed that high activity correlates with strong hydrogen bonding and π–π interactions with key residues. ADMET predictions suggest compounds 3aa and 5fab are promising lead candidates for developing new insecticides.