The molecule is the (S)-enantiomer of 3-hydroxy-3-methyl-2-oxopentanoate. It is a conjugate base of a (S)-3-hydroxy-3-methyl-2-oxopentanoic acid. It is an enantiomer of a (R)-3-hydroxy-3-methyl-2-oxopentanoate.
(3S)-3-hydroxy-3-methyl-2-oxopentanoate