[Chemistry Class Notes] Epimers Pdf for Exam

In the field of stereochemistry, the term Epimer explicitly states one of a pair of stereoisomers.  As per the stereogenic center, the two isomers present in the molecules differ from each other while the remaining remains identical. The Epimers of glucose involve some formations, some examples are starch, glycogen, glucose, polysaccharides, and oligosaccharides.

The stereoisomers β-D-mannopyranose and β-D-glucopyranose are known as epimers because they differ only in the C-2 position of stereochemistry. The hydroxyl group in the β-D-glucopyranose molecule is equatorial (in the “plane” of the ring), whereas, in the β-D-mannopyranose molecule, the C-2 hydroxyl group is axial (up from the “plane” of the ring). These two molecules are known as epimers, but because they do not mirror images of each other, they are not enantiomers.

Enantiomers and Diastereomers

The Enantiomers are also known as Optical isomers, which are two isomers that are relevant to each other by reflection. Let us take a look at the definition of enantiomers and their examples. Enantiomers are non – superimposable and consist of similar physical properties that are expected in a manner they interact with various optical isomers and are related to the other compounds. Hence the different optical isomers can have variant biological effects. The Sedative thalidomide is a very good example of enantiomers.

Diastereomers are also called diastereoisomers, they are a type of stereoisomer. They have been defined as the non-mirror image non-identical stereoisomers. Hence, they are produced when two or more compound stereoisomers have different configurations at either one or more (but not all) of the equivalent or related stereocenters, and they do not mirror images of each other. In case two of the diastereomers differ from each other at only one stereocenter, they are known as epimers. Each of the stereocenters gives rise to two different configurations and thereby increases the stereoisomer’s count by a factor of two. The Diastereomers can vary from the enantiomers in the sense that the latter are stereoisomers pairs that differ in all stereocenters, and therefore they are the exact mirror images of one another. An example of a Diastereomer is Dextro Tartaric Acid.