Microsomal mediated metabolism of dialkylaryltriazenes. II. Isolation and identification of metabolites of 3,3-dimethyl-1-phenyltriazene.

After incubating 3,3-dimethyl-1-phenyltriazene with rat liver microsomes, acetanilid and derivatives of aniline and possibly of 3-methyl-1-phenyltriazene were found as metabolites and identified by mass spectrometry. This is the first time that directly formed metabolites (other than formaldehyde) of a dialkyltriazene were identified. The isolation of a derivative of 3-methyl-1-phenyltriazene as 3-acetyl-3-methyl-1-phenyltriazene supports other evidence that the triazenes are enzymically demethylated. Indication for the formation of phenylhydrazine was also obtained. In addition, hydrolysates of the polar fractions of the incubation mixture contained aniline and 4-hydroxy-aniline as a aglycones.