title: Oleanane saponins from Gymnema sylvestre.
abstract: Six oleanane-type saponins, along with two known triterpene saponins, were isolated from the leaves of Gymnema sylvestre. The structures of the oleanane triterpene glycosides were characterized as longispinogenin 3-O-beta-D-glucuronopyranoside, 21 beta-benzoylsitakisogenin 3-O-beta-D-glucuronopyranoside, 3-O-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl ester, oleanolic acid 3-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranosyl(1-->6)-beta-D- glucopyranoside, 3-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl ester and 3-O-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl oleanolic acid 28-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl ester on the basis of hydrolysis and spectral evidence, including 1D- and 2D-NMR (TOCSY, ROESY, HMQC and HMBC) and FABMS analyses.
authors.affiliation: Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
authors.forename: W C
authors.initials: WC
authors.lastname: Ye
authors.forename: Q W
authors.initials: QW
authors.lastname: Zhang
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: C T
authors.initials: CT
authors.lastname: Che
authors.forename: S X
authors.initials: SX
authors.lastname: Zhao
mesh_terms: D002240:Carbohydrate Sequence; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D012503:Saponins / Q000737:chemistry / Q000302:isolation & purification*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared
chemical_list: D012503:Saponins