Synthesis and stereostructure–activity relationship of three asymmetric center pyrethroids: 2-methyl-3-phenylcyclopropyl-methyl 3-phenoxybenzyl ether and cyanohydrin ester
2-Methyl-3-phenylcyclopropylmethyl 3-phenoxybenzyl ether 2 and cyanohydrinester 3, a couple of pyrethroids with three asymmetric centers, were synthesized. Of each of the four diastereomers of 2 and 3, only the (1R*,2R*,3R*)-2a and 3a showed significant insecticidal activities. Dual sets of enantiomers [(1R,2R,3R)-(-)-2a and (1S,2S,3S)-(+)-2a] and [(1R,2R,3R)-(-)-3a and (1S,2S,3S)-(+)-3a] were synthesized