Construction and Application of Heterocyclic N-xides Possessing the Efficient and Multifunctional Photo-oxidation Capacity

During our search for heterocyclic N-oxides which could serve as an agent for the efficient oxidation of various substrates, without accompanying photochemical intramolecular rearrangements, we found that 1, 3, 7, 9-tetrasubstituted pyrimido [5, 4-g] pteridine-2, 4, 6, 8 (1H, 3H, 7H, 9H) -tetrone 5-oxides are suitable for this purpose. In this review, syntheses, structures, photochemical properties, and applications of the novel heterocyclic N-oxides are described. In particular, it is documented that the excited N-oxides behave as a multifunctional oxidant just like iron-oxenoid species (Fev=O) and also function as a mimic or a generator of active oxygen species.