Wiktionary
dihydrolipoic acid
n. (context organic compound English) The reduced form of lipoic acid.
Wikipedia
Dihydrolipoic acid
Dihydrolipoic acid is an organic compound that is the reduced form of lipoic acid. This carboxylic acid features a pair of thiol groups. It is optically active but only the R-enantiomer is biochemically significant. The lipoic acid/dihydrolipoic acid pair participate in a variety of biochemical transformations.