3-Oxohexanedioic Acid is a degradation product of catechol in the presence of hydrogen peroxide; Also, it is derived from 3-Oxohexanedioic Acid Diethyl Ester (O856830), which is an intermediate used to prepare CMPF (C595000) which is a drug-binding inhibitor which is also a constituent of urine. CMPF can inhibit specific T4 binding in serum by increasing the free concentration of direct competitors.