Cyclic structures of glucose (Anomers):
Glucose forms a hemiacetal between the –CHO group and the –OH group on the C5 atom. As a result, C1 becomes asymmetric (or chiral) and forms two isomers. These two isomers differ in the orientation of -H and –OH groups around C1atom. These isomers are known as α-D-glucose and β-D-glucose. Such pairs of optical isomers which differ in the configuration only around C1 atom are called anomers. The C1 atom is known as anomeric carbon atom.
