The metabolism of N-nitrosomorpholine by rat liver microsomes and its oxidation by the Fenton system

Abstract
The metabolism of N-nitrosomorpholine by rat liver microsomes gave acetaldehyde, formaldehyde, glyoxal and N-nitroso-2-hydroxymorpholine. Oxidation of N-nitroso-morpholine by Fenton's reagent gave acetaldehyde, glycol-aldehyde, glyoxal, (2-hydroxyethoxy)acetaldehyde and N-nitroso-2-hydroxymorpholine. N-Nitroso-3-hydroxymor-pholine was synthesised. In water the new compound gave mainly acetaldehyde, with glycolaldehyde, (2-hydroxy-ethoxy)acetaldehyde and glyoxal. These observations indicated the probability of 3-hydroxylation in the biological and chemical oxidations. N-Nitroso-3-morpholone behaved similarly in water to the 3-hydroxy compound, and gave mainly acetaldehyde, with glycollk acid, (2-hydroxyethoxy)acetic acid and glyoxal. N-Nitroso-3-morpholone and N-nitroso-3-hydroxymorpholine reacted with 3, 4-dichlorobenzenethiol. The action of light or alkali on N-nitrosomorpholine gave glyoxal and labile glyoxal-yielding compounds.