The molecule is an aldehydic acid anion resulting from the deprotonation of the carboxy group of (R)-3-hydroxy-4-oxobutanoic acid. It is an oxo monocarboxylic acid anion and an aldehydic acid anion. It is a conjugate base of a (R)-3-hydroxy-4-oxobutanoic acid.
(3R)-3-hydroxy-4-oxobutanoate