PRODUCTS OF THE REACTION OF CHOLESTEROL WITH HYPOCHLORITE ANION

Products of the reaction of cholesterol with hypochlorite (OCl-) in va rious systems (egg phosphatidylcholine liposomes, low-density lipoprot eins, and aqueous colloidal dispersion of cholesterol) were separated and analyzed by TLC, HPLC, and gas chromatography-mass spectrometry. T he reactions of hypochlorite with cholesterol result in the same react ion products in all treated systems. Eighteen fractions were isolated from the reaction mixture by normal-phase HPLC in hexane-isopropanol ( 95:5 v/v); these were then examined by gas chromatography-mass spectro metry. Six products less polar than cholesterol were isolated from the reaction mixture; two of them were identified as 4,6-cholesten-3-one and 4-cholesten-3,6-dione. Among the oxidation products more polar tha n cholesterol, nine compounds were identified; they are 5,7-cholestadi en-3 beta-ol, 3, 5-cholestadien-7-one, 4-cholesten-3 beta, 6 beta-diol , 5-cholesten-3 beta, 7 beta-diol, cholestan-3 beta, 5 alpha, 6 beta-t riol, 5 alpha-cholestan-3 beta-ol-6-one, 5-cholesten-3 beta-ol-7-one, 5 alpha,6 alpha-epoxycholestan-3 beta-ol, and 5 alpha-cholesten-3,6-di one.