Nitric acid nitroxyl

Nitryl Perchlorate (Nitroxyl Perchlorate). N02C104, mw 145.47, white cryst mp, decomps rapidly at 120° deflagrates on rapid heating Can be prepd by the action of cone nitric acid on perchloric acid ... 

However, the in vivo sources of nitroxyl production remain uncertain. Some authors suggested that nitroxyl anion might be generated by NO synthases [81,82] or during the decomposition of nitrosothiols [83]. It has also been proposed [81] that the primary product of NO synthase is not nitric acid but nitroxyl anion, which is next oxidized by SOD to NO ... 

V,/V-Bis(trifluoromethyl)hydroxylamine (5) is oxidized with potassium permanganate in acetic acid to an interesting free-radical compound, bis(trifluoromethyl)nitroxid-A7-yl(6), a pink-violet gas which condenses to a deep brown-violet liquid.246 Various oxidizing agents are effective in the oxidation of 5 to the corresponding nitroxyl 6.247 The best appears to be cerium(IV) salts either in the solid state or in aqueous acid solution.247 Efficient oxidation processes have been developed using aqueous potassium persulfate solutions, or electrochemical oxidation with cerium(III) nitrate and sodium nitrate in dilute nitric acid.247... 

The oxidation of primary and secondary alcohols by stable organic nitroxyl radicals has been reviewed.111 The kinetics of reactions of alkanes and arenes with peroxynitrous acid suggest the participation of the same active oxidizing species in both gas and aqueous phase HOONO or its decomposition product OONO. 112 The oxidation of the alkaloids reserpine and rescinnamine by nitric acid has been studied.113... 

VII. Nitric Acid, Nitrogen Dioxide, and Nitroxyl Radicals. 341... 

HNO3 (nitric acid) HNO2 (nitrous acid) HNO (nitroxyl). 

In contrast to nitric oxide, which is firmly identified in biological systems and for which numerous (but not all) functions are known, the participation of other nitrogen species in biological processes is still hypothetical. At present, the most interest is drawn to the very reactive nitroxyl anion NOT It has been shown that nitroxyl (or its conjugate acid, HNO)... 

Four routes to form peroxynitrite from nitric oxide. The reaction of nitric oxide with superoxide is only one mechanism leading to the formation of peroxynitrite. Supetoxide could also reduce the nitrosyidioxyl radical. If nitric oxide is directly reduced to nitroxyl anion, it will react with molecular oxygen to form peroxynitrite. At acidic pH, nitrite may form nitrous acid and nitrosonium ion, which reacts with hydrogen peroxide to form peroxynitrite. 

In the biochemical context, it has been well noted that the chemistry of NO (and of its conjugated acid, FINO (i8)) is quite distinct from that of NO (22). Its occurrence in catalytic cycles of NO synthase, nitrite reductase, and nitric oxide reductase (NOR) has been postulated (23). For example, in the multi-iron containing enzyme NOR two NO molecules are converted reductively to nitrous oxide, N2O, with nitroxyl (NO ), and hyponitrite (N202 ) (24) as putative intermediates (23). 

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