Abstract:
Sophoridine is a quinolizidine alkaloid isolated from
Sophora flavescens and
Sophora alopecuroides. Its medical activities include anticancer, anti-inflammation, etc., but little pesticide research. To improve the agricultural value of sophoridine, a series of 15-chloro-18-alkyl (benzyl) oxyiminomethyne derivatives were designed and synthesized through structural modification at C-14 and C-15 positions. Compound
4i (R=4-NO
2Bn) showed good acaricidal activity against female adults of
Tetranychus cinnabarinus. Its 72 h LC
50 value was 0.408 mg/mL, and its acaricidal activity was 8.5 times that of sophoridine (LC
50=3.487 mg/mL). At the concentration of 1 mg/mL, compound
4f (R=4-BrBn) had the best insecticidal activity against
Mythimna separata, with a 35 d corrected mortality rate of 62.3%. These results will provide a basis for using sophoridine derivatives as acaricides and insecticides.