EPIMER

An epimer is a class of stereoisomers, or isomers that have the same bond-to-bond connectivity, yet are not the same compound. Sterioisomers include enantiomers and diastereomers, both which contain a chiral carbon center (excluding geometric isomers, which is a class of diastereomers).

In chemistry, an epimer is a stereoisomer that has a different configuration at only one of several chiral carbon centers. When an epimer becomes in incorporated into a ring structure it is called an anomer. For example, the sugars α-glucose and β-glucose are epimers. In the α-glucose, the -OH group on the first (anomeric) carbon is in the direction opposite the methyl group. In the β-glucose, the -OH group is oriented in the same direction as the methyl group ^[1].

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