Simon metabolites of α-tocopherol are not formed via a rate-controlling scission of the 3′C-H bond

Abstract The major in vivo oxidation products of α-tocopherol, α- T , are the Simon metabolites, 1 and 2 . For these compounds to be formed from α- T the polyisoprenoid tail of α- T must be oxidatively cleaved at the 3′ carbon atom. Comparison of the levels of 2R,4′R,8′R-α-(3′,3′- 2 H 2 )- T and 2R,4′R,8′R-α-[5,7-( C 2 H 3 ) 2 - T remaining in various tissues of rats which had been preloaded with equal quantities of these two forms of vitamin E following a change to a vitamin E-free diet has shown that there is no statistically significant difference in the rates of loss of these two deuterium-labeled α- T 's. This demonstrates that the Simon metabolites are not formed by a rate-controlling scission of the 3′-C-H bond of α- T .