(±)-Mandelic-2,3,4,5,6-d5 Acid is a deuterated compound of (±)-Mandelic Acid. (±)-Mandelic Acid has a CAS number of 90-64-2. It is an isomer of cresotinic acid (2-hydroxy-3-methylbenzoic acid) and oxymethylbenzoic acid (2-methoxybenzoic acid). Derivatives of mandelic acid are formed as a result of metabolism of adrenaline and noradrenaline by monoamine oxidase and catechol-o-methyl transferase. It is also present in certain skin care products, is an intermediate molecule in the production of other biochemicals, may be used as an analytical reagent and is a precursor in the manufacture of dyes. Mandelic acid is found to be associated with phenylketonuria, which is an inborn error of metabolism.