title: Pregnane glycosides, gymnepregosides A-F from the roots of Gymnema alternifolium.
abstract: The structural elucidation of six new related polyoxypregnane glycosides, gymnepregosides A (1), B (2), C (3), D (4), E (5) and F (6), together with two known compounds, from the roots of Gymnema alternifolium (Asclepiadaceae) was achieved through on a detailed study of 1H- and 13C-NMR spectral data and chemical means. The results obtained for new compounds, 1-6, show that they are (20S)-pregn-6-ene-3 beta,5 alpha,8 beta,12 beta,14 beta,17 beta,20-heptaol or sarcostin 3-O-glycosides, and all the sugars at C-3 are beta(1-->4)-linked. Some of them possessed benzoyl, cinnamoyl and tigloyl residues as the ester linkages located at C-12 and/or C-20 of the aglycon.
authors.affiliation: Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yoshikawa
authors.forename: K
authors.initials: K
authors.lastname: Matsuchika
authors.forename: S
authors.initials: S
authors.lastname: Arihara
authors.forename: H C
authors.initials: HC
authors.lastname: Chang
authors.forename: J D
authors.initials: JD
authors.lastname: Wang
mesh_terms: D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification*; D018517:Plant Roots / Q000737:chemistry; D011278:Pregnanes / Q000737:chemistry* / Q000302:isolation & purification*; D016339:Spectrometry, Mass, Fast Atom Bombardment
chemical_list: D006027:Glycosides; D010936:Plant Extracts; D011278:Pregnanes