Epimers are diastereoisomers that have the opposite configuration at only one of two or more chiral centers present in the respective molecular entities. For example D-glucose and D-mannose, which differ only in the stereochemistry at C-2, are epimers, as are D-glucose and D-galactose (which differ at C-4).
Generalic, Eni. "Epimer." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. 1 Apr. 2025. <https://glossary.periodni.com>.
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Periodic Table