Indolinonic aminoxyls can effectively scavenge various radicals by directly coupling with them or by imitating superoxide dismutase. To better understand the radical-coupling reactions, DFT method B3LYP/6-31G(d,p) wa...Indolinonic aminoxyls can effectively scavenge various radicals by directly coupling with them or by imitating superoxide dismutase. To better understand the radical-coupling reactions, DFT method B3LYP/6-31G(d,p) was employed to calculate variations of free energy for the coupling reactions and other physico-chemical parameters. The radical-coupling activity difference between aminoxyls was elucidated to a large extent in terms of electronic properties of substituents.展开更多
To elucidate the different lipid-oxidation potentials of aminoxylantioxidants, a kind of combined density functional theory (DFT) method was employed to calculateC―H bond dissociation enthalpies (BDEs) of a model lin...To elucidate the different lipid-oxidation potentials of aminoxylantioxidants, a kind of combined density functional theory (DFT) method was employed to calculateC―H bond dissociation enthalpies (BDEs) of a model linoleic acid (LH) and O―H BDEs of hydrogenatedaminoxyls. The higher the O―H BDE is, the more potent the aminoxyl to abstract the H-atom from LHand the stronger the LH-oxidation potential. Accordingly, the prooxidant activity differences ofaminoxyls were elucidated by the different O―H BDEs of hydrogenated aminoxyls, which were furtherclarified in terms of distinct electronic effects of the substituents.展开更多
This review article summarizes the electron transfer reactions of piperidine aminoxyl radicals. Electrochemical studies revealed the single electron transfer nature of piperidine aminoxyl radicals. In solution, piperi...This review article summarizes the electron transfer reactions of piperidine aminoxyl radicals. Electrochemical studies revealed the single electron transfer nature of piperidine aminoxyl radicals. In solution, piperidine aminoxyl radicals serve as single electron transfer oxidation reagent to react with various biologically interesting molecules such as glutathione, cysteine, ascorbic acid, and amines. The reaction product distribution, reaction kinetics, intermediates, and the reaction features in biological mimic environments including micelles and cyclodextrins were investigated. Oxoammonium salts, the one-electron transfer oxidation products of piperidine aminoxyl radicals, are agents of organic synthesis to selectively generate ketones or di-ketones from alcohols or ketones bearing α-methylene group under mild conditions. The new reactions of oxoammonium salts with aromatic amines, phenols, heterocycles including phenothiazines, papaverine, and bilirubin are also illustrated.展开更多
基金This study was supported by the National Natural Science Foundation of China (Grant No. 30100035).
文摘Indolinonic aminoxyls can effectively scavenge various radicals by directly coupling with them or by imitating superoxide dismutase. To better understand the radical-coupling reactions, DFT method B3LYP/6-31G(d,p) was employed to calculate variations of free energy for the coupling reactions and other physico-chemical parameters. The radical-coupling activity difference between aminoxyls was elucidated to a large extent in terms of electronic properties of substituents.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .3 0 10 0 0 3 5 )
文摘To elucidate the different lipid-oxidation potentials of aminoxylantioxidants, a kind of combined density functional theory (DFT) method was employed to calculateC―H bond dissociation enthalpies (BDEs) of a model linoleic acid (LH) and O―H BDEs of hydrogenatedaminoxyls. The higher the O―H BDE is, the more potent the aminoxyl to abstract the H-atom from LHand the stronger the LH-oxidation potential. Accordingly, the prooxidant activity differences ofaminoxyls were elucidated by the different O―H BDEs of hydrogenated aminoxyls, which were furtherclarified in terms of distinct electronic effects of the substituents.
基金supported by the National Natural Science Foundation of China
文摘This review article summarizes the electron transfer reactions of piperidine aminoxyl radicals. Electrochemical studies revealed the single electron transfer nature of piperidine aminoxyl radicals. In solution, piperidine aminoxyl radicals serve as single electron transfer oxidation reagent to react with various biologically interesting molecules such as glutathione, cysteine, ascorbic acid, and amines. The reaction product distribution, reaction kinetics, intermediates, and the reaction features in biological mimic environments including micelles and cyclodextrins were investigated. Oxoammonium salts, the one-electron transfer oxidation products of piperidine aminoxyl radicals, are agents of organic synthesis to selectively generate ketones or di-ketones from alcohols or ketones bearing α-methylene group under mild conditions. The new reactions of oxoammonium salts with aromatic amines, phenols, heterocycles including phenothiazines, papaverine, and bilirubin are also illustrated.
