102564-44-3Relevant academic research and scientific papers
Comparative metabolism of N-tert-butyl-N-[1-(1-oxy-pyridin-4-yl)-ethyl]- and N-tert-butyl-N-(1-phenyl-ethyl)-nitroxide by the cytochrome P450 monooxygenase system
Novakov, Christo P.,Stoyanovsky, Detcho A.
, p. 749 - 753 (2002)
The use of spin-trapping agents for a direct ESR detection of ·OH in biological systems is limited by the low stability of the hydroxyl radical-derived nitroxides. Among the various probes used for trapping of ·OH, DMSO has proven to be highly efficient.
An ESR and HPLC-EC assay for the detection of alkyl radicals
Novakov,Feierman,Cederbaum,Stoyanovsky
, p. 1239 - 1246 (2007/10/03)
The correlation of lipid peroxidation with release of alkanes (RH) is considered a noninvasive method for the in vivo evaluation of oxidative stress. The formation of RH is believed to reflect a lipid hydroperoxide (LOOH)-dependent generation of alkoxyl radicals (LO·) that undergo β-scission with release of alkyl radicals (R·). Alternatively, R· could be spin-trapped with a nitrone before the formation of RH and analyzed by ESR. Extracts from the liver and lung of CCl4- and asbestos-treated rats that were previously loaded with nitrones exhibited ESR spectra suggesting the formation of iso-propyl, n-butyl, ethyl, and pentyl radical-derived nitroxides. In biological systems, various nitroxides with indistinguishable ESR spectra could be formed. Hence, experiments with N-tert-butyl-α-phenylnitrone (PBN) for spin trapping of R· were carried out in which the nitroxides formed were separated and analyzed by HPLC with electrochemical detection (EC). The C1-5 homologous series of PBN nitroxides and hydroxylamines were synthesized, characterized by ESR, GC-MS, and HPLC-EC, and used as HPLC standards. For in vivo generation and spin trapping of R·, rats were loaded with CCl4 and PBN. The HPLC-EC chromatograms of liver extracts from CCl4-treated rats demonstrated the formation of both the nitroxide and hydroxylamine forms of PBN/·CCl3, as well as the formation of a series of unidentified PBN nitroxides and hydroxylamines. However, formation of PBN adducts with retention times similar to these of the PBN/C2-5 derivatives was not observed. In conclusion, we could not correlate the production of PBN-detectable alkyl radicals with the reported CCl4-dependent production of C1-5 alkanes. We speculate that the major reason for this is the low steady-state concentrations of R· produced because only a small fraction of LO· undergo β-scission to release R·.
Synthesis of Hindered Secondary Amines via Grignard Reagent Addition to Ketonitrones
Schwartz, Martin A.,Hu, Xiufeng
, p. 1689 - 1692 (2007/10/02)
Grignard reagents add to ketonitrones in a nonpolar solvent to afford N,N-dialkylhydroxylamines in good yields and with little competing proton transfer.Deoxygenation of the crude hydroxylamines with carbon disulfide then completes an efficient general sy
Tungstate-Catalyzed Oxidation of Secondary Amines to Nitrones. α-Substitution of Secondary Amines via Nitrones
Murahashi, Shun-Ichi,Mitsui, Hitoshi,Shiota, Tatsuki,Tsuda, Tomoyasu,Watanabe, Shoji
, p. 1736 - 1744 (2007/10/02)
The sodium tungstate catalyzed oxidation of secondary amines with hydrogen peroxide gives the corresponding nitrones.Acyclic and cyclic nitrones can be obtained from secondary amines in a single step in good to escellent yields.The oxidation of secondary amines in the presence of alkenes gives isoxazolidines by 1,3-dipolar cycloaddition of nitrones.Introduction of a substituent at the α-position of secondary amines can be performed upon oxidation of secondary amines and subsequent treatment with various nucleophiles.
