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The stereochemistry of the hydrogen elimination in the biological conversion of cholest-7-en-3-beta-ol into cholesterol.

ABSTRACT: 1. The syntheses of Delta(7)-[4-(14)C]cholestenol (XVI, Scheme 3) and Delta(7)-[6alpha-(3)H]-cholestenol (XII, Scheme 2) are described. 2. The metabolism of doubly labelled Delta(7)-cholestenol (II, Scheme 1) by rat-liver homogenates was studied. 3. During the enzymic conversion of Delta(7)-cholestenol into cholesterol (IV, Scheme 1) the 6alpha-hydrogen atom of the former is lost and the overall reaction corresponds to a cis-elimination. 4. In the light of these results various mechanisms for the conversion of Delta(7)-cholestenol into cholesterol are discussed.

SUBMITTER: Akhtar M

PROVIDER: S-EPMC1270267 | biostudies-other | 1967 Feb

REPOSITORIES: biostudies-other

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The conversion of cholest-5-en-3beta-ol into cholest-7-en-3beta-ol by the echinoderms Asterias rubens and Solaster papposus.

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The conversion of cholest-7-en-3beta-ol into cholesterol. General comments on the mechanism of the introduction of double bonds in enzymic reactions.

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