1,2,4-Triazine N-oxides and their annelated derivatives

This review deals with the synthesis and properties of 1,2,4-triazine N-oxides and their annelated derivatives. Methods for the incorporation of the N-oxide group in the 1,2,4-triazine ring by direct oxidation and cyclisation involving nitro, nitroso, and isonitroso groups are discussed. Reactions of 1,2,4-triazine N-oxides with electrophiles, nucleophiles, and dicnophilcs are considered. The effect of the N-oxide group on the chemical shifts in the 1H, 13C, and 14N NMR spectra and the specific features of decomposition of 1,2,4-triazine N-oxides under elec-tron impact are analysed. © 1998 Russian Academy of Sciences and Turpion Ltd.