The chiral pyrethroid cycloprothrin: stereoisomer synthesis and separation and stereoselective insecticidal activity
Biao Jiang1, Hua Wang, Qun-Mei Fu
1Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China. jiamgb@mail.sioc.ac.cn
Abstract:
The synthesis and separation of the isomers of the pesticide cycloprothrin have been realized for the first time. Complete separation was achieved on a DAICEL CHIRALCEL OJ-H column (25 x 0.46 cm) for (1R, alpha*)-cycloprothrin isomers and on a DAICEL CHIRALCEL OD-H column (25 x 0.46 cm()) for (1S, alpha*)-cycloprothrin isomers. The insecticidal activity of (1R, alphaR)-cycloprothrin for the larvae of Mythimaseparata and Aphismedicagini was found to be about six times and four times higher, respectively, than that of racemic cycloprothrin.
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