Diphenyl nitric oxide

For the free radical, diphenyl nitric oxide, the presence of a neutral tetravalent nitrogen has been suggested (/). It will be clear... 

The development of DFT computations of electronic g-tensors has mainly focused on improving the accuracy and applicability for isolated systems, while only little attention has been devoted to account for environmental effects. Most studies of solvent or matrix effects on electronic g-tensors have adopted the supermolecular approach, in which the solvent molecules are explicitly introduced into the model used in the calculations. Recently, we developed an electronic g-tensor formalism in which solvent effects are accounted for by the polarizable continuum model [154]. We applied this approach to investigate solvent effects on electronic g-tensors of di-r-butyl nitric oxide (N-I) and diphenyl nitric oxide (N-II). Calculations were... 

Just as for the semiquinones, rearrangement of spin density within a nitroxide should lead to a modification of the g-values. As the polarity of the solvent is increased, the spin density on oxygen decreases and so the g-value should shift towards the free-spin value of 2.00232. An experimental study of the g-value of diphenyl nitric oxide confirms this expectation, in carbon tetrachloride g was found to be 2.00572 0.00005, while in water g was 2.00502 0.00005. Hiickel molecular orbital calculations were used to reproduce the spin density distributions in the various solvents and hence to determine the modification in the Coulomb-integral parameter for oxygen produced by solvation. Theoretical g -shifts were then calculated and from the difference between the experimental and theoretical g-shifts, an estimate was made of the solvent dependence of the tt transition. This estimate was in reasonable agreement with the experimentally determined variation of the energy of this band in the various solvents employed. 

Figure 5. Molecular structures of the diphenyl nitric oxide (DPNO) and di-ieri-butyl nitric oxide (DTBNO) radicals, and the g-tensor orientation. The largest component g points along the N-O bond. Reproduced with permission from [133]. Copyright 2006, American Chemical Society.

Table 4. Calculated g-Shifts for the Diphenyl Nitric Oxide Radical DPNO in Water or Methanol (MeOH), Including Explicit Solvent Molecules...

Tetraphenylhydrazine is a while solid, soluble in chloroform, acetone, benzene, or toluene, and upon standing is changed into triphenylaminc plus azobenzene. In solution, tetraphenylhydrazine dissociates into nitrogen diphenyl. (Ct,Hs) N-. free radical, which in toluene at 90cC reads with nitric oxide, NO, Tetraphenylhydrazine is formed by oxidation of diphenylamine,. by lead dioxide. 

Japanese scientists believe that the anti-oketsu effects of rhubarb are brought about by the inhibition of the production of nitric oxide, inhibition of platelet aggregation, antiallergic effects, and its antiinflammatory properties. Matsuda et al. (2001) studied and reported that the methanolic extracts from five kinds of rhubarb were found to show scavenging activity for l,l-diphenyl-2-picrylhy-drazyl (DPPH) radical and superoxide anion radical (02 ) generated by the xanthine/xanthine oxidase system and/or on lipid peroxidation by terf-butyl hydroperoxide (f-BuOOH) in the erythrocyte membrane ghost system. 

Several phenolic diterpenoids with antioxidant activities were isolated from rosemary leaves. These include camosol, camosic acid, rosmanol, isorosmanol, and epirosmanol. Camosol showed potent antioxidative activity as revealed by scavenging a,a-diphenyl-(3-picrylhydrazyl free radicals and protection of oxidative DNA damage. In chronic inflammation, cytokines induce the production of nitric oxide, which is converted to DNA-damaging and carcinogenic peroxynitrite. Peroxynitrite is a cytotoxicant with... 

Indazoles may be assembled via thermolysis as well. Treatment of diphenylcarbamoyl chloride with sodium azide gives rise to diphenyl-carbamoyl azide. Thermolysis of the diphenyl-carbamoyl azide then afforded indazolol. Subsequent alkylation of the indazolol then produced a series of indazole derivatives as activators of the nitric oxide receptor, soluble guanylate cyclise. 

Carbamoyl methyl Phosphine Oxide Derivatives The physicochemical properties of various aryl derivatives of CMPO have been investigated at the Vernadsky Institute of Geochemistry and Analytical Chemistry. Extraction of americium and lanthanides from nitric acid with solutions of diphenyl- and dibutyl-(diethylcarbamoylmethyl) phosphine oxides (Ph2Et2-CMPO and Bu2Et2-CMPO) in dichloroethane have been investigated as a function of the concentrations of the extractants and nitric acid (110, 111). The observed dependences are characterized... 

Kulyako, Y.M., Maliko, D.A., Chmutova, M.K., Litvina, M.N., Myasoedov, B.F. 1998. New method for actinide and rare-earth element recovery by diphenyl[dibutylcarbamoyl-methyljphosphine oxide from nitric acid solutions. Journal of Alloys and Compounds 271-273 760-764. 

Oxidizing agents such as nitric acid, air, hydrogen peroxide, and lead tetraacetate convert ditellurium compounds to tellurinic acid derivatives. Diphenyl ditellurium suspended in hot dilute nitric acid formed benzenetellurinic acid nitrate5. Air oxidizes dissolved diaryl ditellurium compounds to tellurinic acid anhydrides6. Diphenyl ditellurium and lead tetraacetate in benzene solution form phenyl tellurium triacetate7,8. 

---