Non-food bioactive products for insecticides (II): Insights into agricultural activities of matrine-type alkaloid analogs as botanical pesticides

To explore candidate pesticides from non-food bioactive products, twenty-five new matrine-type alkaloid analogs, 15-chloro-18-(acyl)oximinylmatrines (6a–6y), were semi-synthesized from matrine isolated from the roots of Sophora flavescens Aiton (Fabaceae). The spatial configurations of six derivatives were determined by X-ray crystallography. Analogs 6f (R = (CH2)9CH3) and 6g (R = (CH2)10CH3) all showing the pronounced insecticidal and acaricidal activities against two threatening pests Mythimna separata Walker and Tetranychus cinnabarinus Boisduval, could be used as the lead compounds for further structural optimization. It suggested that R as the aliphatic alkane with long straight chain was necessary for the insecticidal and acaricidal activities of matrine oximino esters.