An analysis of the various methods of producing pure enatiomeric drugs.
This paper discusses how ever since the ?Thalidomide? incidence last century there has been an ever-increasing amount of resources injected into optical isomeric research and in attaining pure enantiomeric products. It shows how due to different stereochemical characteristics, different isomers will have different interactions with biological receptors in the body, giving rise to different actions. A resultant undesirable effect is therefore inherently possible upon the consumption of chiral drugs, for that reason it is imperative that the end drug mixture is as entiomerically pure as possible. It describes the 3 basic methodologies for single enantiomers: chirality pool, kinetic resolution and asymmetric synthesis and examines the basis of and the techniques of separating them.
“One way of the use of chirality pool molecules merely requires the maintenance of pre-existing chirality throughout a synthesis, with transformation of other parts of the molecule by formation of new chemical bonds or inter-conversion of functional groups. Otherwise, utilising chirality pool can afford a so-called “control element” for the creation of new stereogenic centres by “substrate-directable” reactions. Such reactions may involve complete transfer of chirality from one region to another intra-molecularly.”