title: Potential bile acid metabolites. 20. A new synthetic route to stereoisomeric 3,6-dihydroxy- and 6-hydroxy-5 alpha-cholanoic acids.
abstract: An improved procedure for the syntheses of stereoisomeric 3,6-dihydroxy- and 6-hydroxy-5 alpha-cholanoic acids (and their methyl esters) is described. The principal reactions employed are those reported in the preceding paper of this series, with the commercially available hyodeoxycholic acid as starting material. The final step in the procedure is the reduction of the key 5 alpha C-6 ketones with either the stereoselective equatorial reagent, Li/NH3/MeOH, or the axial reagent, Zn(BH4)2. The results of analysis of the prepared 6-monohydroxylated and 3,6-dihydroxylated stereoisomers by thin-layer chromatographic, high performance liquid chromatographic and gas-liquid chromatographic mobilities, and 1H and 13C nuclear magnetic resonance spectra are discussed along with the data for the corresponding compounds in the 5 beta-series.
authors.affiliation: College of Engineering, Nihon University, Fukushima, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Iida
authors.forename: T
authors.initials: T
authors.lastname: Tamaru
authors.forename: F C
authors.initials: FC
authors.lastname: Chang
authors.forename: T
authors.initials: T
authors.lastname: Niwa
authors.forename: J
authors.initials: J
authors.lastname: Goto
authors.forename: T
authors.initials: T
authors.lastname: Nambara
mesh_terms: D001647:Bile Acids and Salts / Q000378:metabolism*; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003840:Deoxycholic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010084:Oxidation-Reduction; D013237:Stereoisomerism
chemical_list: D001647:Bile Acids and Salts; D007202:Indicators and Reagents; D003840:Deoxycholic Acid; C083588:6-hydroxycholanoic acid; C010471:hyodeoxycholic acid