EPR Study on Stable Magnesium Complexes of the Phenoxyl Radicals Derived from a Vitamin E Model and Its Deuterated Derivatives

• Nakanishi Ikuo

  Redox Regulation Research Group, Research Center for Radiation Safety, National Institute of Radiological Sciences Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Agency

• Matsumoto Shigenobu

  Tokyo Metropolitan Institute of Gerontology

• Ohkubo Kei

  Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Agency

• Fukuhara Kiyoshi

  Division of Organic Chemistry, National Institute of Health Sciences

• Okuda Haruhiro

  Division of Organic Chemistry, National Institute of Health Sciences

• Inami Keiko

  Division of Organic and Bioorganic Chemistry, Kyoritsu College of Pharmacy

• Mochizuki Masataka

  Division of Organic and Bioorganic Chemistry, Kyoritsu College of Pharmacy

• Ozawa Toshihiko

  Redox Regulation Research Group, Research Center for Radiation Safety, National Institute of Radiological Sciences

• Itoh Shinobu

  Department of Chemistry, Graduate School of Science, Osaka City University

• Fukuzumi Shunichi

  Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Agency

• Ikota Nobuo

  Redox Regulation Research Group, Research Center for Radiation Safety, National Institute of Radiological Sciences

Abstract

The phenoxyl radical 1^•, generated by the reaction of a vitamin E model, 2,2,5,7,8-pentamethylchroman-6-ol (1H), with 2,2-bis(4-tert-octylphenyl)-1-picrylhydrazyl (DOPPH^•), was significantly stabilized by complex formation with Mg²⁺ in deaerated acetonitrile at 298 K. The assignments of the hyperfine coupling constants (hfc) obtained by computer simulations of the observed EPR spectrum of the Mg²⁺ complex of 1^• (Mg²⁺–1^•), were carried out using three deuterated isotopomers of 1^•, i.e., 5-CD₃-1^•, 7-CD₃-1^•, and 8-CD₃-1^•, where a methyl group at the C5, C7, or C8 position is replaced by a CD₃ group, respectively. The decreased spin density of the benzene ring in the Mg²⁺–1^• complex indicates that delocalization of the unpaired electron in 1^• into Mg²⁺ by complexation between Mg²⁺ and 1^• results in the enhanced stability of 1^• in the presence of Mg²⁺.

Journal

• Bulletin of the Chemical Society of Japan

  Bulletin of the Chemical Society of Japan 77 (9), 1741-1744, 2004

  The Chemical Society of Japan

Keywords

• General Chemistry

Details

• CRID: 1390001204129388800
• NII Article ID: 130004151769
• NII Article ID: 10013584659
• NII Book ID: AA00580132
• DOI: 10.1246/bcsj.77.1741
• ISSN: 13480634
• ISSN: 00092673
• NDL BIB ID: 7077211
• Web Site: http://id.ndl.go.jp/bib/7077211
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I7077211
• Web Site: https://academic.oup.com/bcsj/article-pdf/77/9/1741/56264268/bcsj.77.1741.pdf
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed