Development of novel nitroxyl radicals for controlling reactivity with ascorbic acid

Yuichi Kinoshita, Ken Ichi Yamada, Toshihide Yamasaki, Hiromi Sadasue, Kiyoshi Sakai, Hideo Utsumi

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

Piperidine and pyrrolidine nitroxyl radicals (nitroxide) contain unpaired electrons and have been widely recognized as antioxidants, contrast agents, spin probes, radiation protective agents and polymerization mediators. Nitroxyl radicals can react with free radicals and reductants and their reactivities depend on the basic structure of the nitroxyl radicals themselves. However, reductants easily reduce these radicals and they lose their paramagnetic nature and function. Therefore, the aim of this study was to develop various functional nitroxyl radicals, particularly focusing on stability towards AsA through the improvement of the synthetic route for a series of 2,6-substituted nitroxyl radicals. Tetraethyl-substituted piperidine nitroxyl radical 8 exhibited resistance to AsA reduction and 2,6-dispiro-4′,4″-dipyrane-piperidin-4-one-N-oxyl 5 had a second-order rate constant 10-times greater than those of hydroxyl-TEMPO and oxo-TEMPO. The 2,6-substituted compound offers various reactivities towards AsA and the possibility to be used as a new antioxidant, contrast agent and radical polymerizer.

Original languageEnglish
Pages (from-to)565-571
Number of pages7
JournalFree Radical Research
Volume43
Issue number6
DOIs
Publication statusPublished - Jul 27 2009

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Ascorbic Acid
Reducing Agents
Contrast Media
Antioxidants
Radiation-Protective Agents
nitroxyl
Polymerization
Hydroxyl Radical
Free Radicals
Rate constants
Electrons

All Science Journal Classification (ASJC) codes

  • Biochemistry

Cite this

Development of novel nitroxyl radicals for controlling reactivity with ascorbic acid. / Kinoshita, Yuichi; Yamada, Ken Ichi; Yamasaki, Toshihide; Sadasue, Hiromi; Sakai, Kiyoshi; Utsumi, Hideo.

In: Free Radical Research, Vol. 43, No. 6, 27.07.2009, p. 565-571.

Research output: Contribution to journalArticle

Kinoshita, Yuichi ; Yamada, Ken Ichi ; Yamasaki, Toshihide ; Sadasue, Hiromi ; Sakai, Kiyoshi ; Utsumi, Hideo. / Development of novel nitroxyl radicals for controlling reactivity with ascorbic acid. In: Free Radical Research. 2009 ; Vol. 43, No. 6. pp. 565-571.
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