Nitrous acid with nitric oxide

Suzuki, T., Yamaoka, R., Nishi, M., Ide, H., and Makino, K. (1996) Isolation and characterization of a novel product, 2 -deoxyoxanosine, from 2 -deoxyguano-sine, oligodeoxynucleotide, and calf thymus DNA treated with nitrous acid and nitric oxide. J. Am. Chem. Soc., 118, 2515-2516. 

Sakamaki, F., S. Hatakeyama, and H. Akimoto (1983). Formation of nitrous acid and nitric oxide in the heterogeneous dark reaction of nitrogen dioxide with water vapor in a smog chamber. Int. J. Chem. Kinet. 15, 1013-1029. 

The structure of the major photoproduct of irradiation of the dinucleotide d(TpA) and TA containing oligonucleotides has been re-characterised. 2 -Deoxyoxoanosine (218) has been isolated from calf thymus DNA after treatment with the mutagens nitrous acid or nitric oxide. ... 

Nitric oxide is made commercially by oxidation of ammonia above 500°C in the presence of platinum, or by reduction of nitrous acid with ferrous sulphate or feiTous halides. The physical ... 

Nitrogen dioxide reacts with water, giving first a mixture of nitrous and nitric acids, and ultimately nitric acid and nitric oxide ... 

Deamination of 2-amino-2-deoxy-D-idonolactone (27) with nitrous acid led, after oxidation with nitric acid, to 2,5-anhydro-D-glucaric acid39,42 (28). As deamination of 2-amino-2-deoxy-D-idonic acid, followed by oxidation, gave 2,5-anhydro-D-idaric acid, the different behavior of the lactone 27 must be due to an attack on the incipient carbonium-ion at C-2 by a favorably disposed hydroxyl group in the molecule, such as at C-5. 

The relatively acidic thiol on serum albumin forms a fairly stable S-nitroso adduct with nitric oxide, which may serve to preserve and carry NO throughout the circulatory system [162,163]. Bacterial toxins released in toxic-shock syndrome induce excessive NO-synthase activity in macrophages. The resulting arterial expansion may induce the cardiovascular collapse associated with toxic shock syndrome [164]. Nitrous acid reacts with DNA to form dG-N2-dG interstrand crosslinks at the sequence 5 CG [165]. NO can also deaminate cytidine [166] and deoxyguanosine [167] and so may function as a mutagen. The rate law for NO reacting with O2 has been measured electrochemically as [168] ... 

At low acid concentrations, nitric oxide tends to form. This evidently may attack nitrosophenol to form diazonium compounds directly. The diazonium salts, in turn, may couple with unreacted phenol to give colored products. Nitrous acid may also produce nitrophenols from phenols. The mechanism of this reaction may involve oxidation of initially formed nitrosophenols, homolytic attack by nitrogen dioxide, or nucleophilic attack by nitrite ions [1]. 

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