2-hydroxy-3-phenylpropanoic acid

(S)-2-Hydroxy-3-phenylpropanoic acid (L-(−)-3-Phenyllactic acid) is a chiral aromatic compound involved in phenylalanine metabolism. It is likely produced from phenylpyruvate via lactate dehydrogenase. The D-form is derived from bacterial sources, while the L-form is endogenous. Phenyllactate levels are normally very low in blood or urine, but high levels indicate phenylketonuria (PKU) and hyperphenylalaninemia (HPA). PKU is due to a deficiency of phenylalanine hydroxylase (PAH), causing phenylalanine to convert to phenylpyruvic acid rather than tyrosine.

3-Phenyllactic acid (PhLA) is a broad spectrum antimicrobial compound active against bacteria and fungi, DL-3-Phenyllactic acid (3-Phenyllactic acid) is a reagent involved in biological studies of nantioselectivity of lipase in transesterification and oxidation by glycolate oxidase and catalase.

(2S,3S)-3-Hydroxy-2-methyl-3-phenylpropanoic acid is a chemical synthesis intermediate.