title: 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.
authors.affiliation: Integrative Biosciences Graduate Program, The Pennsylvania State University, University Park, USA.
authors.forename: Qi
authors.initials: Q
authors.lastname: Sun
authors.forename: Sutang
authors.initials: S
authors.lastname: Cai
authors.forename: Blake R
authors.initials: BR
authors.lastname: Peterson
mesh_terms: D002782:Cholestenes / Q000138:chemical synthesis* / Q000737:chemistry; D020650:Combinatorial Chemistry Techniques; D006845:Hydrocarbons, Fluorinated / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism; D013256:Steroids / Q000737:chemistry*; D013329:Structure-Activity Relationship
chemical_list: D002782:Cholestenes; D006845:Hydrocarbons, Fluorinated; D013256:Steroids