Question

What are anomers?

Answer 1

Hint: We need to write about anomers. It is mentioned in the chapter biomolecules. They are a type of epimers differing at acetal and hemiacetal carbons.

Complete step by step answer:
Anomers are cyclic monosaccharides or glycosides that are epimers, differing from each other in the configuration of C-1 if they are aldoses or in the configuration at C-2 if they are ketoses.
An anomer is actually an epimer (also a cyclic saccharide) which differs in configuration, particularly at the acetal or hemiacetal carbon (refer to the image below to differentiate between acetal and hemiacetal carbons).
Example of anomers is $ \alpha - D - {\text{Glucopyranose and }}\beta - D - {\text{glucopyranose}} $
Alpha and beta anomers are formed from an open-chain sugar by mutarotation. In the process of mutarotation, a solution of both anomers is heated at a high temperature, giving rise to individual monomers. $ \alpha - D - {\text{Glucopyranose and }}\beta - D - {\text{glucopyranose}} $ .

Additional Information :
The two anomers of glucose are mentioned here. Glucose is both an aldehyde at C-1 and an alcohol at C-5. These two groups can react with each other to form a cyclic hemiacetal (glucopyranose). ... These two isomers are anomers, and C-1 (the original carbonyl carbon) is the anomeric carbon.
Both epimers and anomers are stereoisomers; in fact, anomers are a special case of epimers. The main difference between them is that epimers differ in configuration at only one chiral (stereo genic) centre, but anomers differ in configuration, especially at the acetal or hemiacetal carbon.

Note:
An anomer is a type of geometric variation found at certain atoms in carbohydrate molecules. An epimer is a stereoisomer that differs in configuration at any single stereo genic centre. An anomer is an epimer at the hemiacetal/acetal carbon in a cyclic saccharide, an atom called the anomeric carbon.