The body of living organisms are composed of many enantiopure chiral substances. For example, amino acids that make up the proteins in the body have the same configuration, L-absolute configuration. Because of this specificity, vital processes such as constructing proteins, rely on stereoselectivity to ensure that out of all the potential enantiomers available, the body is utilizing the correct enantiopure compound.
Selectivity is a very important part of organic synthesis. In scientific papers regarding synthesis, selectivity is often listed in data tables alongside percent yield and other reaction conditions. While selectivity is deemed important in scientific literature, it has been challenging to effectively implement selectivity in drug development and production. A major issue with selectivity in pharmaceuticals is that a large percentage of drug syntheses by nature are not selective reactions, racemic mixtures are formed as the products. Separating racemic mixtures into their respective enantiomers takes extra time, money, and energy. One way to separate enantiomers is to chemically convert them into species that can be separated: diastereomers. Diastereomers, unlike enantiomers, have entirely different physical properties—boiling points, melting points, NMR shifts, solubilities—and they can be separated by conventional means such as chromatography or recrystallization. This is a whole extra step in the synthesis process and not desirable from a manufacturing standpoint. As a result, a number of pharmaceuticals are synthesized and marketed as a racemic mixture of enantiomers in cases where the less-effective enantiomer is benign. However, by identifying and specifically purifying the enantiomer which effectively binds to its respective binding site in the body, less of the drug would be needed to achieve the desired effect. With the improvement of chiral technology, a rich repertoire of enantioselective chromatographic methods have become available for the separation of drug enantiomers on the analytical, preparative, and industrial scales.