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 (<b>FL</b>) derivatives using an active substructure splicing strategy. Their insecticidal activities were evaluated against key pests, including <i>Myzus persicae</i>, <i>Bemisia tabaci</i> and <i>Tetranychus urticae</i><i>.</i> The LC₅₀ values of compounds <b>3ea</b>, <b>3fa</b>, <b>3ga</b>, and <b>5cab</b> against <i>B. tabaci</i> were 69.8 mg/L, 186 mg/L, 91.9 mg/L, and 112 mg/L, respectively. For <i>M. persicae</i>, the <b>LC</b>_<b>50</b> values of compounds <b>3aa</b>, <b>5gaa</b>, and <b>5fab</b> were 5.31 mg/L, 5.43 mg/L, and 4.67 mg/L, respectively, with compound <b>5fab</b> exhibiting significantly better activity than the reference <b>FL</b> (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 <b>3aa</b> and <b>5fab</b> are promising lead candidates for developing new insecticides.