Reaction of arylnitroso compounds with mercaptans.

1. The non-enzymic reactions of trans-4-nitrosostilbene, 4-nitrosobibenzyl, 2-nitrosofluorene and p-nitrosotoluene with glutathione were studied. 2. Three types of reaction products have been identified, namely, the corresponding hydroxylamine, amine, and a water-soluble adduct which hydrolyses under acidic or alkaline conditions to an amine and glutathione sulphinic acid. 3. Reduction to the amine is explained by formation of adducts which are reduced by glutathione with the production of oxidized glutathione. 4. The relevance of this reaction for metabolic activation and inactivation of aromatic amines in vivo is discussed.