New Synthetic Method and Insecticidal Activities of Novel Imidazopyridine Mesoionic Derivatives Containing an Ester Group
Zhengjun Liu, Runjiang Song, Desheng Zhang, Rong Wu, Ting Liu, Zheng-Xue Wu, Baoan Song
Abstract
To develop novel insecticides with high efficiency, a new mode of action, and safety to nontarget organisms and the environment, a series of imidazopyridine mesoionic compounds containing an ester group have been designed and synthesized via a new synthetic method discovered by our group. The bioactivity results showed that most of the target compounds exhibited significant insecticidal activities against Aphis craccivora, and some of them showed moderate insecticidal activities against Sogatella furcifera. Among them, compounds C2, C4–C11, and D3 showed excellent insecticidal activities against A. craccivora (LC50 values were lower than 4.5 μg/mL), which were superior to those of pymetrozine (LC50 = 6.19 μg/mL) and triflumezopyrim (LC50 = 4.68 μg/mL). Remarkably, the insecticidal activity of compound C9 was 5.9-fold greater than that of triflumezopyrim with an LC50 value of 0.8 μg/mL. Proteomics and molecular docking results indicated that compound C9 may affect the nervous system of A. craccivora and act on nicotinic acetylcholine receptors like triflumezopyrim.