Non-food bioactive products for pesticides candidates (III): Agricultural properties of isoxazole esters from the plant product podophyllotoxin as botanical pesticides

Due to their structural diversity and biological characteristics, natural products appear to be received much attention as lead compounds. Podophyllotoxin, a naturally sustainable aryltetralin lignan, is isolated from the roots and rhizomes of Podophyllum hexandrum. To discover new potentially natural product-based pesticidal agents, a series of isoxazole esters were regioselectively prepared by structural modification of podophyllotoxin. Compared with their precursor podophyllotoxin, compounds IId, IIIc and IIId exhibited the potent insecticidal activity, and compounds IIb, IIc, IIIc and IIId showed the pronounced acaricidal activity; especially compounds IIIc (X = Cl, R = 4-ClC6H4) and IIId (X = Cl, R = 4-FC6H4) exhibited the most promising pesticidal activities against Mythimna separata Walker and Tetranychus cinnabarinus Boisduval. [Display omitted] •A series of isoxazole esters were regioselectively prepared by structural modification of podophyllotoxin.•Analogs IId, IIIc and IIId exhibited potent the insecticidal activity of their precursor podophyllotoxin.•Analogs IIb, IIc, IIIc and IIId showed the pronounced acaricidal activity of podophyllotoxin.•Analogs IIIc and IIId exhibited the most potent insecticidal and acaricidal activities against Mythimna separata and Tetranychus cinnabarinus.