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The use of symmetry in enantioselective synthesis: four pairs of chrysene enantiomers prepared from 19-nortestosterone.

ABSTRACT: Expansion of the D-ring of 19-norsteroids with incorporation of the steroid C-18 methyl group into a newly formed six-membered ring provides easy access to the chrysene ring system. By taking advantage of the symmetry of the chrysene ring system and avoiding meso chrysene intermediates, four optically pure 2,8-difunctionalized (C-2 hydroxyl group and C-8 oxo group) hexadecahydrochrysene diastereomers, and their corresponding optically pure enantiomers were prepared from 19-nortestosterone. The eight chrysene stereoisomers are of interest as starting materials for preparing chrysene analogues of physiologically important neurosteroids.

SUBMITTER: Stastna E

PROVIDER: S-EPMC3154374 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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The use of symmetry in enantioselective synthesis: four pairs of chrysene enantiomers prepared from 19-nortestosterone.

Stastna Eva E Rath Nigam P NP Covey Douglas F DF

Organic & biomolecular chemistry 20110503 12

Expansion of the D-ring of 19-norsteroids with incorporation of the steroid C-18 methyl group into a newly formed six-membered ring provides easy access to the chrysene ring system. By taking advantage of the symmetry of the chrysene ring system and avoiding meso chrysene intermediates, four optically pure 2,8-difunctionalized (C-2 hydroxyl group and C-8 oxo group) hexadecahydrochrysene diastereomers, and their corresponding optically pure enantiomers were prepared from 19-nortestosterone. The e ...[more]

PMID: 21541379

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