Nitric oxide exchange

Nitric Oxide. Rates of nitric oxide exchange with CoI(NO)2(PPh3) in toluene solution are much greater than for nitric oxide exchange with Co(CO)3(NO) or with Fe(CO)2(NO)a in the gas phase. The reaction in toluene is zero-order in nitric oxide concentration, but in the gas phase the reaction is first-order in nitric oxide. A fuller understanding of these rate and rate-law differences may develop when the preliminary report on the solution studies is amplified in the promised full version which will include activation parameters. 

Sodium nitrite has been synthesized by a number of chemical reactions involving the reduction of sodium nitrate [7631-99-4] NaNO. These include exposure to heat, light, and ionizing radiation (2), addition of lead metal to fused sodium nitrate at 400—450°C (2), reaction of the nitrate in the presence of sodium ferrate and nitric oxide at - 400° C (2), contacting molten sodium nitrate with hydrogen (7), and electrolytic reduction of sodium nitrate in a cell having a cation-exchange membrane, rhodium-plated titanium anode, and lead cathode (8). 

Iwamoto, M., Yokoo, S., Sakai, K. el al. (1981) Catalytic decomposition of nitric oxide over copper(II)-exchanged Y-type zeolites, J. Chem. Soc. Faraday Trans., 77, 1629. 

Tajima, N., Hashimoto, M., Toyama, F. et al. (1999) A theoretical study on the catalysis of Cu-exchanged zeolite for the decomposition of nitric oxide, Phys. Chem. Chem. Phys., 1, 3823. 

The characteristics of the four major classes of histamine receptors are summarized. Question marks indicate suggestions from the literature that have not been confirmed. AA, arachidonic acid DAG, diacylglycerol Iko,2+, calcium-activated potassium current IP3, inositol 1,4,5-trisphosphate NHE, sodium-proton exchange, PKC, protein kinase C NO, nitric oxide PTPLC, phosphoinositide-specific phospholipase C TXA2, thromboxane A2. Has brain-penetrating characteristics after systemic administration. 

The NO/NO+ and NO/NO- self-exchange rates are quite slow (42). Therefore, the kinetics of nitric oxide electron transfer reactions are strongly affected by transition metal complexes, particularly by those that are labile and redox active which can serve to promote these reactions. Although iron is the most important metal target for nitric oxide in mammalian biology, other metal centers might also react with NO. For example, both cobalt (in the form of cobalamin) (43,44) and copper (in the form of different types of copper proteins) (45) have been identified as potential NO targets. In addition, a substantial fraction of the bacterial nitrite reductases (which catalyze reduction of NO2 to NO) are copper enzymes (46). The interactions of NO with such metal centers continue to be rich for further exploration. 

Burch, R. and Scire, S. Selective catalytic reduction of nitric oxide with ethane and methane on some metal exchanged ZSM-5 zeolites. Appl. Catal, B Environmental,... 

Long, R. Q. and Yang, R. T. Selective Catalytic reduction of nitric oxide with ethylene on copper ion-exchanged Al-MCM-41 catalyst, Ind. Eng. Chem. Res., 1999, Volume 38, Issue 3, 873-878. 

Long, C. J., Shikano, K., and Berkowitz, B. A. (1987). Anion exchange resins discriminate between nitric oxide and EDRF. Eur. J. Pharmacol. 142, 317-318. 

The work of Ye et al. (1991) was extended to include Tn5 mutants in nir genes for nitrite reductase of Pseudomonas fluorescens (Ye etal., 1992a) and Pseudomonas sp. strain G-179 (Ye et al., 1992b) which use, respectively, the cytochrome cd - and Cu-type nitrite reductase. The five mutants of P. fluorescens characterized not only lacked nitrite reductase and N0/H20- 0 exchange activities, but also showed levels of nitric oxide reductase activity that were diminished roughly by a factor of two. The reason for the decrease in nitric oxide reductase activity of the mutants is not clear, but may represent a change in... 

As far as we know, nitric oxide reductase has not been shown to catalyze the N0/H20-" 0 exchange reaction. 

Braun, C., and Zumft, W. G. (1991). Marker exchange of the structural genes for nitric oxide reductase blocks the denitrification pathway of Pseudomonas stutzeri at nitric oxide. . Biol. Chem. 266, 22785-22788. 

Firestone, M. K., Firestone, R. B., and Tiedje, ]. M. (1979). Nitric oxide as an intermediate in denitrification Evidence from nitrogen-13 isotope exchange. Biochem. Biophys. Res. Commun. 91, 10-16. 

Ruggiero, C. E., Carrier, S. M., Antholine, W. E., Whittaker, J. W., Cramer, C. J., and Tolman, W. B. (1993). Synthesis and structure and spectroscopic characterization of mononuclear copper nitrosyl complexes Models for nitric oxide adducts of copper proteins and copper exchange zeolites. J. Am. Chem. Soc. 115, 11285-11298. 

Ye, R. W., Toro-Suarez, 1., Tiedje, J. M., and Averill, B. A. (1991). H2 0 isotope exchange studies on the mechanism of reduction of nitric oxide and nitrite to nitrous oxide by denitrifying bacteria. J. Biol. Chem. 266, 12848-12851. 

Basco and Norrish25 flash photolyzed C2N2 and BrCN in the presence of NO and observed vibrationally excited nitric oxide. They suggested that it was formed through near-resonance vibration-vibration energy exchange with CN radicals and/or in the photolysis of NCNO. 

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