Synthesis and Evaluation O-Benzyl Oxime-ether Derivatives Containing β-Methoxyacrylate Moiety for Insecticidal and Fungicidal Activities

Abstract

In attempt to lead compounds exhibiting both insecticidal and fungicidal activities, a series of O-benzyl oximeether derivatives were designed and synthesized by introducing <TEX>${\beta}$</TEX>-methoxyacrylate pharmacophore into a scaffold. The insecticidal activity against Aphis fabae and the fungicidal activity against Erysiphe graminis were screened. The title compounds exhibited remarkable insecticidal and fungicidal activities. The most potent compound 6d was identified. Its insecticidal <TEX>$LC_{50}$</TEX> against A. fabae is 6.4 mg/L, which is lower than that of chlorfenapyr (19.4 mg/L) and even close to the level of imidacloprid (4.8 mg/L). Its fungicidal <TEX>$EC_{90}$</TEX> in preventive and curative treatment against E. graminis are 2.2 and 4.8 mg/L, respectively, which are lower than azoxystrobin (7.0 and 5.9 mg/L). These results indicate that compound 6d can be considered as a lead for further developing new O-benzyl oxime-ether typed candidates with both fungicidal and insecticidal activities.