4. Modes of action of biostereoselectivity

Biological stereoselectivity results from a number of steric complementarities. The half-life of enantiomers, for example, includes different rates of binding to transport proteins, and of interaction with several other chiral systems, immunological, receptor or enzymatic, enzyme or hormone targets of pesticidal action and metabolizing enzymes. In the case of diastereoisomers, hydrophobic/hydrophilic interactions will also differ. Biosynthesized products behave like those derived from chemical synthesis when administered to foreign organisms, and/or in non-physiological doses or introduced via non-physiological routes.

Today, pure stereoisomers are produced thanks to the availability of chiral catalysts including enzymes, and the use of pre-elaborated chiral building blocks or synthons. However, data on the individual properties of members of stereoisomer families...