Studies on the 7V-Hydroxylation and Carcinogenicity of 4-Aminoazo- beiizene and Related Compounds'

gens in the neoplastic processes induced by these compounds. The fact that the aromatic aminoazo dyes are carcinogenic primarily in the liver and generally not at sites of local application (16) has suggested that the aminoazo dyes are likewise active through the formation of reactive metabolites. The structural similarity be tween the aminoazo dyes and the carcinogenic aromatic amines and amides suggested that these reactive metabolites might be Ar-hydroxy derivatives.