574732-12-0Relevant articles and documents
Reactions of peroxynitrite with γ-tocopherol
Hoglen, Niel C.,Waller, Stephen C.,Sipes, I. Glenn,Liebler, Daniel C.
, p. 401 - 407 (2007/10/03)
The reaction of peroxynitrite with γ-tocopherol (γ-TH) in a methanol/potassium phosphate buffer solution results in the formation of four major products, which were identified as 2,7,8-trimethyl-2-(4,8,12- trimethyldecyl)-5-nitro-6-chromanol (NGT), 2,7,8-trimethyl-2-(4,8,12- trimethyldecyl)-5,6-chromaquinone (tocored), and two diastereomers of 8a- (hydroxy)-γ-tocopherone. NGT was the major product formed in these reactions, and its formation was modestly increased by increasing amounts of Fe3+-EDTA. Tocored and NGT also were formed when γ-TH was exposed to 3- morpholinosydnonimine (SIN-1), a compound that decomposes to form peroxynitrite. When γ-TH reacted with the nitrating agent NO2+BF4- in acetonitrile or methanol/potassium phosphate buffer, NGT and tocored also were formed, but the major product detected was γ-tocopherol quinone (γ- TQ). This product was not detected in reactions involving peroxynitrite. Oxidation of γ-TH by peroxynitrite involves nitration and electron transfer reactions. Since the product distribution in oxidations with NO2+BF4- differed substantially from that in oxidations with peroxynitrite and SIN-1, NO2+ appeared not to be the principal species involved in NGT formation. Nitration of γ-TH may involve either peroxynitrite or some peroxynitrite- derived oxidant other than NO2+. Because of its stability and formation as a novel product of the reaction between γ-TH with peroxynitrite, NGT may be a useful in vivo marker for peroxynitrite interactions with lipid structures that contain γ-TH.
