Synthesis and Insecticidal Activities of Novel Nitrogenous Derivatives of Celangulin-V

Abstract

In order to develop new biorational pesticides and clarify the potential structural factors needed for the biological activity of celangulin-V analogues, thirty novel nitrogenous derivatives were designed and synthesized. The single crystal structure of celangulin-V is reported for the first time and provides a more accurate structure than that previously reported. The structures of all the new derivatives were confirmed by either NMR or ESI-MSⁿ analysis. Insecticidal activities of these compounds were tested against the third-instar larvae of Mythimna separata. One derivative (1–6) showed higher insecticidal activity than celangulin-V, with a KD₅₀ of 231.2 μg.g^–1, while two compounds (2–13 and 2–14) exhibited lower insecticidal activities; the others revealed no activity at a concentration of 20 mg mL⁻¹. The results support the view that celangulin-V has the potential to be a lead structure of semi-synthetic green insecticides.