Iminoxyl radicals

Recently, Gunther et al. [41] proposed that nitric oxide may directly react with enzymes without intermediate formation of peroxynitrite. It is known that the oxidation of arachido-nic acid by prostaglandin H oxidase is mediated by the formation of enzyme tyrosyl radical (see Chapter 26). Correspondingly, it has been suggested that NO is able to react with this radical to form the tyrosine iminoxyl radical and then nitrotyrosine. Therefore, the NO-dependent nitration of protein tyrosine residue may occur without the formation of peroxynitrite or other nitrogen oxides. 

JOC3524). Bis(iminoxyl) radicals are postulated as precursors since it is known that oximes generate iminoxyl radicals under oxidative conditions (Section 4.36.4.9.2) (73CRV93). 

The recombination of radicals with nitric oxide gives nitroso compoimds that imdergo isomerisation into oximes [11] to produce iminoxyl radicals in the reaction with NO2 ... 

Salts have been prepared of 249 by oxidation of the heterocycle with SbClj, UClg, and MoOC. The perchlorate of 3,7-dimethoxy-phenothiazine cation-radical was prepared by oxidation using iminoxyl radicals in organic solvents followed by treatment with perchloric acid. " Various salts of 261 and its benzo derivatives and of lO-phenylphenothiazine were prepared by oxidation with iodine and the appropriate silver salt, " and radical salts of phenothiazine drugs have been made by oxidation of the heterocycles with the acid whose counterion was used for the salt perchlorate and sulfate. ... 

Heterocyclic iminoxyl radicals, applications for synthesis of spin-labeled... 

Heterocyclic iminoxyl radicals for trapping of other radicals 80APO(17)1. N-Heterocyclic stable radicals in kinetic study of radical polymerization ... 

Stable iminoxyl radicals of imidazoline series, application of 83KFZ658. Stable iminoxyl radicals of imidazoline series, synthesis and reactivity of ... 

Rozantsev, E. G. "Free Iminoxyl Radicals," Khimiya, Moscow, 1970. 

Yu.B. Shilov, R.M. Battalova, and E.T. Denisov, Regeneration of iminoxyl radical during polypropylene oxidation, Doklad. Acad. Nauk USSR 1972, 207, 388-389. 

Yu.B. Shilov and E.T. Denisov, Mechanism of the inhibiting activity of iminoxyl radicals during oxidation of polypropylene and polyethylene, Vysokomol. Soyed. A 1974,74(10), 2313-2316. 

Indazoles.- Acetone hydrazone is transformed into 3-methylindazole (274) on treat-ment with butyllithium. Oxidation of the oxime (275) with lead(IV) acetate generates the iminoxyl radical (276), which yields 2,3-diphenylindazole (277). 

Radical polymerisation of fluoroalkyl methacrylates CH2=C(CH3)COOCH2-(CF2-CF2) ,-R, where R = H (I) or CH3 (II), m = 1,2, 3, in the presence of stable iminoxyl radicals was studied [76]. Study of the induction stage indicates that secondary inhibition observed is performed by the catalytic mechanism without using the secondary inhibitor effects... 

Iminoxyl radicals which are stable in air and are easily synthesized in chemically pure state (mainly, crystalline brightly-colored substances) present a principally new... 

Unsaturated ketoximes underwent oxyoximation using teri-butyl nitrite (TBN) as the iminoxyl radical initiator as well as the carbon radical trap. The NO-trapped isoxazolines spontaneously dimerized under the reaction conditions and were converted into isoxazoline carbaldehyde oximes by treatment with Et3N at 80°C (10 examples 82—93% yield). For example, the two-step... 

Decay of phenoxyl radicals is accompanied by appearance of iminoxyl radicals (Fig. 4). 

Change in the iminoxyl radical concentration in the course of thermolysis of lignin exposed to NO2 at room temperature. Figure 5 gives information about concentration of iminoxyl radicals at different temperatures. 

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