Abstract
Two isomers of primary products formed by methylene blue sensitized photooxidation of δ-tocopherol were separated by thin layer chromatography. The products were characterized by UV, IR and NMR spectra and were identified to be 8aS- and SaR-hydroperoxy δ-tocopheryl dienones, respectively. On decomposition of the photooxidized α-, ϒ;- and δ-tocopherols, to-copheryl quinone and tocopheryl quinone epoxide were formed. The effect of hydroperoxy δ-tocopheryl dienone on methyl linoleate peroxidation was examined. The hydroperoxy dienone formed by the photooxidation of tocopherols did not accelerate lipid peroxidation.