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Peroxynitrite

In today's world, Peroxynitrite has become a topic of great relevance and interest to a wide spectrum of society. Whether due to its impact on culture, economics, politics or science, Peroxynitrite has managed to capture the attention of millions of people around the world. Its influence extends to different areas and its study and understanding have become fundamental to understanding current dynamics. In this article, we will delve into the fascinating world of Peroxynitrite, exploring its different facets and analyzing its importance in contemporary society.

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Peroxynitrite
Chemical structure of the peroxynitrite anion
Names
IUPAC name
Oxido nitrite
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
674445
KEGG
UNII
  • InChI=1S/HNO3/c2-1-4-3/h3H/p-1
    Key: CMFNMSMUKZHDEY-UHFFFAOYSA-M
  • N(=O)O
Properties
NO3−
Molar mass 62.005 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa).
Reactions of peroxynitrite leading to either apoptotic or necrotic cell death

Peroxynitrite (sometimes called peroxonitrite) is an ion with the formula ONOO−. It is a structural isomer of nitrate, NO−
3. Peroxynitrite is a potent reactive nitrogen species and is highly cytotoxic.[1]

Preparation

Peroxynitrite can be prepared by the reaction of superoxide with nitric oxide:[2][3][4]

NO + O−2 → NO(O2)−

It is prepared by the reaction of hydrogen peroxide with nitrite:[5]

H2O2 + NO−
2 → ONOO− + H2O

Its presence is indicated by the absorbance at 302 nm (pH 12, ε302 = 1670 M−1 cm−1).

Reactions

Peroxynitrite is weakly basic with a pKa of ~6.8.

It is reactive toward DNA and proteins.

ONOO− reacts nucleophilically with carbon dioxide.[6] In vivo, the concentration of carbon dioxide is about 1 mM, and its reaction with ONOO− occurs quickly. Thus, under physiological conditions, the reaction of ONOO− with carbon dioxide to form nitrosoperoxycarbonate (ONOOCO−
2) is by far the predominant pathway for ONOO−. ONOOCO−
2 homolyzes to form carbonate radical and nitrogen dioxide, again as a pair of caged radicals. Approximately 66% of the time, these two radicals recombine to form carbon dioxide and nitrate. The other 33% of the time, these two radicals escape the solvent cage and become free radicals. It is these radicals (carbonate radical and nitrogen dioxide) that are believed to cause peroxynitrite-related cellular damage.

Peroxynitrous acid

Main article: Peroxynitrous acid

Its conjugate acid peroxynitrous acid is highly reactive, although peroxynitrite is stable in basic solutions.[7][8]

See also

References

  1. ^ Szabó, Csaba; Ischiropoulos, Harry; Radi, Rafael (August 2007). "Peroxynitrite: biochemistry, pathophysiology and development of therapeutics". Nature Reviews Drug Discovery. 6 (8): 662–680. doi:10.1038/nrd2222. ISSN 1474-1784.
  2. ^ Bohle, D. Scott; Sagan, Elisabeth S. (2004). "Main Group Compounds". Tetramethylammonium Salts of Superoxide and Peroxynitrite. Inorganic Syntheses. Vol. 34. p. 36. doi:10.1002/0471653683.ch1. ISBN 978-0-471-64750-8.
  3. ^ Pacher, P; Beckman, J. S; Liaudet, L (2007). "Nitric oxide and peroxynitrite in health and disease". Physiological Reviews. 87 (1): 315–424. doi:10.1152/physrev.00029.2006. PMC 2248324. PMID 17237348.
  4. ^ Szabó, C; Ischiropoulos, H; Radi, R (2007). "Peroxynitrite: Biochemistry, pathophysiology and development of therapeutics". Nature Reviews Drug Discovery. 6 (8): 662–80. doi:10.1038/nrd2222. PMID 17667957.
  5. ^ Beckman, J. S; Koppenol, W. H (1996). "Nitric oxide, superoxide, and peroxynitrite: The good, the bad, and ugly". American Journal of Physiology. Cell Physiology. 271 (5 Pt 1): C1424–37. doi:10.1152/ajpcell.1996.271.5.C1424. PMID 8944624.
  6. ^ Denicola, Ana; Freeman, Bruce A.; Trujillo, Madia; Radi, Rafael (1996-09-01). "Peroxynitrite Reaction with Carbon Dioxide/Bicarbonate: Kinetics and Influence on Peroxynitrite-Mediated Oxidations". Archives of Biochemistry and Biophysics. 333 (1): 49–58. doi:10.1006/abbi.1996.0363. ISSN 0003-9861.
  7. ^ Holleman, A. F.; Wiberg, E. Inorganic Chemistry Academic Press: San Diego, 2001. ISBN 0-12-352651-5.
  8. ^ Koppenol, W. H (1998). "The chemistry of peroxynitrite, a biological toxin". Química Nova. 21 (3): 326–331. doi:10.1590/S0100-40421998000300014.
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