Doubly allylic hydroperoxide formed in the reaction between sterol 5,7-dienes and singlet oxygen

Albro, PW; Corbett, JT; Schroeder, JL

HERO ID

1399886

Reference Type

Journal Article

Year

1994

Language

English

PMID

7991659

HERO ID 1399886
In Press No
Year 1994
Title Doubly allylic hydroperoxide formed in the reaction between sterol 5,7-dienes and singlet oxygen
Authors Albro, PW; Corbett, JT; Schroeder, JL
Journal Photochemistry and Photobiology
Volume 60
Issue 4
Page Numbers 310-315
Abstract Ergosterol and 7-dehydrocholesterol, common 5,7-conjugated diene sterols, react with photochemically produced singlet oxygen very efficiently to yield, in parallel pathways, the corresponding 5,8-endoperoxides and the 7 beta-hydroperoxy-5,8(9),22-trienol or -5,8(9)-dienol, respectively. The hydroperoxides decompose in an acid-catalyzed reaction to generate hydrogen peroxide and the 5,7,9(11),22-tetraenol or 5,7,9(11) trienol, respectively, with 1:1 stochiometry. The molar ratio of endoperoxide to hydroperoxide was constant (16:5) with two different reaction solvents, two different photosensitizers, and at all time points between 5 min and 3 h from the start of irradiation. Ergosterol did not react with either hydrogen peroxide or superoxide ion under our reaction conditions. Inhibition studies with nitrogen, 2,5-dimethylfuran, beta-carotene, and tert-butanol confirmed the involvement of singlet oxygen in these reactions. The unstable hydroperoxide would be expected to have undesirable biological consequences if formed in vivo.
Pmid 7991659
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English