Abstract The chemistry of N-hydroxyguanidines, focusing on photo-sensitized oxygenation and reaction with nitric oxide (NO), was examined. In the former reaction, a urea derivative was obtained as the main product together with the generation of NO. On the other hand, in the latter case, oxidative nitrosation occurred under aerobic conditions to give a nitrosourea derivative, which was also obtained from urea by the same treatment.
