Sterol metabolism. XLI. Cholesterol A-ring autoxidations

Ghulam Ansari, Leland L. Smith

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Chromatographic and spectral evidence is adduced for the presence of cholest-5-en-3-one, cholest-4-en-3-one, and cholest-4-ene-3,6-dione in samples of cholesterol aged naturally in air or subjected to irradiation in air by 60Co gamma radiation. These findings establish an additional mode of air oxidation of cholesterol to A-ring 3-ketones. Moreover, the oxidation by air of cholest-5-en-3-one induced by 60Co gamma radiation yielded cholest-4-en-3-one, cholest-4-ene-3,6-dione, and the epimeric 3-oxocholest-4-ene-6-hydroperoxides. Cholest-4-en-3-one was not altered by irradiation in air, nor was cholesterol isomerized to cholest-4-en-3β-ol upon irradiation. From these observations it is deduced that the radiation-induced A-ring dehydrogenation of cholesterol yields initially cholest-5-en-3-one which upon isomerization yields cholest-4-en-3-one not further oxidized and which by a second oxidation yields the epimeric 3-oxocholest-4-ene-6-hydroperoxides which decompose to cholest-4-ene-3,6-dione.

Original languageEnglish (US)
Pages (from-to)55-62
Number of pages8
JournalChemistry and Physics of Lipids
Volume22
Issue number1
DOIs
StatePublished - 1978

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Sterols
Metabolism
Cholesterol
Air
Gamma Rays
Irradiation
Gamma rays
Oxidation
Hydrogen Peroxide
Dehydrogenation
Isomerization
Ketones
Radiation
cholest-4-en-3-one
cholest-5-en-3-one

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics

Cite this

Sterol metabolism. XLI. Cholesterol A-ring autoxidations. / Ansari, Ghulam; Smith, Leland L.

In: Chemistry and Physics of Lipids, Vol. 22, No. 1, 1978, p. 55-62.

Research output: Contribution to journalArticle

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