Pyrethroid insecticides, stereochemistry

S-Bioallethrin (Fig. 5 ]9a]) is a S)mthetic pyrethroid insecticide with three asymmetric centers. The S designation refers to the l-K, 3-R, 4 -S isomer and is not a true designation of stereochemistry. Conversion of the terminal allylic group to —CHjCHjCHjOH, formation of hemisuccinate. 

Synthetic pyrethroid insecticides are photostable analogs of the natural pyrethrins of botanical origin they consist of a series of related esters derived from alcohols and acids that maintain critical isosteric relations with the natural product prototype. Small changes in substituents and stereochemistry are sufficient... 

The usefulness of this transformation first became apparent when it was discovered that some chiral cyclopropane-containing pyrethroids were highly effective insecticides. More importantly, the biological activity of these compounds was directly related to the cyclopropane stereochemistry [4]. One of the most ef-... 

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