ChEBI: 3,4-dihydroxyphenylpyruvic acid is a 2-oxo monocarboxylic acid that is pyruvic acid in which one of the methyl hydrogens is substituted by a 3,4-dihydroxyphenyl group. It has a role as a metabolite. It is functionally related to a pyruvic acid. It is a conjugate acid of a 3,4-dihydroxyphenylpyruvate.