What are Anomers?

Anomers are cyclic monosaccharides which differ from one another in the configuration of C-1 or C-2 carbon.

A pair of anomers, which differ only at the carbon bearing the aldehyde or ketone functional group in the sugar's open-chain form, are two nearly identical stereoisomers in the study of carbohydrates. Since the anomeric carbon is planar and achiral in open-chain form, anomers can only occur when the sugar is in its cyclic form. In a cyclic saccharide, an anomer is an epimer at the hemiacetal/hemiketal carbon, to put it more precisely. The process of changing one anomer into another is known as anomerization. Various anomers have different physical characteristics, melting points, and particular rotations, as is normal for stereoisomeric substances.

The process of changing one anomer into another is known as anomerization. Anomerization, also known as mutarotation, happens easily in solution and is catalysed by acid and base in the case of reducing sugars. This reversible process often results in an anomeric combination where the two separate anomers eventually approach equilibrium.