Reaction between cholesterol in aqueous sodium stearate dispersions and H2O2 yielded many products of which 1 2 were isolated and identified. Products included 5, 6α-epoxy-5α-cholestan-3β-ol and 5, 6β-epoxy-5β-cholestan-3β-oI in 1:8 ratio representing direct reaction between cholesterol and H2O2 and 5α-cholestane-3β,5, 6β-triol formed by hydration of the 5, 6-epoxides; epimeric cholesterol 7-hydroperoxides, epimeric cholest-5-ene-3β,7-diols, and 3β-hydroxycholest-5-en-7-one representing free-radical oxidation of cholesterol by molecular oxygen derived by H2O2 disproportionation; 5α-cholest-6-ene-3β, 5-diol, cholest-4, 6-dien-3-one, and 7α-stearatoxycholest-5-en-3β-ol possibly derived from singlet molecular oxygen released in H2O2 disproportionation: and 5α-cholestane-3β, 6β-diol. These results complete our studies of reactions between cholesterol and dioxygen species, revealing fr the first time the several pathways of oxidation of a biologically important substrate by dioxygen species.
ASJC Scopus subject areas
- Colloid and Surface Chemistry