Synthesis and spin-trapping behavior of 5-ChEPMPO, a cholesteryl ester analogue of the spin trap DEPMPO

J Org Chem. 2005 Dec 9;70(25):10426-33. doi: 10.1021/jo0517390.

Abstract

[structure: see text] 5-(Cholesteryloxyethoxyphosphoryl)-5-methylpyrroline N-oxide (5-ChEPMPO), a DEPMPO analogue bearing a cholesterol group on the phosphorus atom, has been prepared and used to trap peroxyl-, alkoxyl-, thiyl-, and carbon-centered radicals in organic solvent. The important steric hindrance in 5-ChEPMPO does not affect the properties of 5-ChEPMPO in comparison to DEPMPO for the spin trapping of an enantiopure linoleic acid hydroperoxide. The 5-ChEPMPO-OOL spin adduct was observed by ESR and confirmed by ESI-MS/MS experiments. The relaxation terms of the 5-ChEPMPO-lipid peroxyl spin adduct were compared with those of other peroxyl spin adducts, and it was shown that the cholesteryl group has only a weak influence on the exchange rate between adduct conformers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cholesterol / analogs & derivatives*
  • Cholesterol / chemical synthesis
  • Cholesterol / chemistry
  • Cholesterol Esters / chemical synthesis*
  • Electron Spin Resonance Spectroscopy
  • Linoleic Acids
  • Lipid Peroxides
  • Mass Spectrometry
  • Pyrroles / chemical synthesis*
  • Pyrroles / chemistry*
  • Spin Labels / chemical synthesis*
  • Spin Trapping*

Substances

  • (diethoxyphosphoryl)-5-methylpyrroline N-oxide
  • 2-ethoxycarbonyl-2-methyl-3,4-dihydro-2H-pyrrole-1-oxide
  • 5-(cholesteryloxyethoxyphosphoryl)-5-methylpyrroline N-oxide
  • Cholesterol Esters
  • Linoleic Acids
  • Lipid Peroxides
  • Pyrroles
  • Spin Labels
  • linoleic acid hydroperoxide
  • Cholesterol