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.