Collect. Czech. Chem. Commun. 1994, 59, 2727-2733

Identification of 1-(3,4-Dihydroxyphenylazo)-2-hydroxynaphthalene as the Product of Oxidation of 1-Phenylazo-2-hydroxynaphthalene (Sudan I, Solvent Yellow 14) by Rat Liver Microsomes

Marie Stiborov√°a, Befekadu Asfawa, Eva Freib, Heinz H. Schmeiserb and Manfred Wiesslerb

a Department of Biochemistry, Charles University, 128 40 Prague 2, Czech Republic
b Department of Molecular Toxicology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany


The carcinogenic azo dye 1-phenylazo-2-hydroxynaphthalene (Sudan I, Solvent Yellow 14) is oxidized by rat liver microsomes to a number of azo-containing metabolites. One of the products of hitherto unknown structure has been shown to be identical with 1-(3,4-dihydroxyphenylazo)-2-hydroxynaphthalene. The identification of this product completed the pattern of major products of Sudan I oxidation by microsomal cytochrome P-450.