title: Determination of C-23 configuration in (20R)-23-hydroxycholestane side chain of steroid compounds by 1H and 13C NMR spectroscopy.
abstract: Epimeric (20R,23R)- and (20R,23S)-23-hydroxycholestane steroids were synthesized. Their structures were elucidated by extensive 1H and 13C NMR spectroscopy and application of the Mosher's method. All proton and carbon signals of the side chains were assigned. Based on these assignments spectral data allow the determination of the C-23 stereochemistry of (20R)-23-hydroxycholestane side chains of the new natural steroids by comparison with spectra of the obtained model compounds. As a result, the C-23 configuration of two steroid compounds from the starfishes Lethasterias nanimensis chelifera and Lethasterias fusca was established.
authors.affiliation: G.B Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok 690022, Russia. kicha@piboc.dvo.ru
authors.forename: Alla A
authors.initials: AA
authors.lastname: Kicha
authors.forename: Anatoly I
authors.initials: AI
authors.lastname: Kalinovsky
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Antonov
authors.forename: Oleg S
authors.initials: OS
authors.lastname: Radchenko
authors.forename: Natalia V
authors.initials: NV
authors.lastname: Ivanchina
authors.forename: Timofey V
authors.initials: TV
authors.lastname: Malyarenko
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Savchenko
authors.forename: Valentin A
authors.initials: VA
authors.lastname: Stonik
mesh_terms: D000818:Animals; D002777:Cholestanols / Q000138:chemical synthesis*; D015394:Molecular Structure; D013215:Starfish / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D002777:Cholestanols