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Practical synthesis of 3beta-amino-5-cholestene and related 3beta-halides involving i-steroid and retro-i-steroid rearrangements.

ABSTRACT: Derivatives of 3beta-amino-5-cholestene (3beta-cholesterylamine) are of substantial interest as cellular probes and have potential medicinal applications. However, existing syntheses of 3beta-amino-5-cholestene are of limited preparative utility. We report here a practical method for the stereoselective preparation of 3beta-amino-5-cholestene, 3beta-chloro-5-cholestene, 3beta-bromo-5-cholestene, and 3beta-iodo-5-cholestene from inexpensive cholesterol. A sequential i-steroid/retro-i-steroid rearrangement promoted by boron trifluoride etherate and trimethylsilyl azide converted cholest-5-en-3beta-ol methanesulfonate to 3beta-azido-cholest-5-ene with retention of configuration in 93% yield.

SUBMITTER: Sun Q

PROVIDER: S-EPMC2651230 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Practical synthesis of 3beta-amino-5-cholestene and related 3beta-halides involving i-steroid and retro-i-steroid rearrangements.

Sun Qi Q Cai Sutang S Peterson Blake R BR

Organic letters 20090201 3

Derivatives of 3beta-amino-5-cholestene (3beta-cholesterylamine) are of substantial interest as cellular probes and have potential medicinal applications. However, existing syntheses of 3beta-amino-5-cholestene are of limited preparative utility. We report here a practical method for the stereoselective preparation of 3beta-amino-5-cholestene, 3beta-chloro-5-cholestene, 3beta-bromo-5-cholestene, and 3beta-iodo-5-cholestene from inexpensive cholesterol. A sequential i-steroid/retro-i-steroid rear ...[more]

PMID: 19115840

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