https://doi.org/10.1351/goldbook.R05224
Compounds containing an enediol structure stabilized by @C01267@ and hydrogen bonding with an adjacent carbonyl group, RC(OH)=C(OH)C(=O)R. They are strong reducing agents, fairly strong acids and commonly derived from @S05441@ by @O04362@ at the carbon atom alpha to the carbonyl function, e.g. ascorbic acid.