title: New cyanogenic and alkyl glycoside constituents from Phyllagathis rotundifolia.
abstract: Methanolic extracts of the leaves, stems, and roots of Phyllagathis rotundifolia collected in Malaysia yielded seven galloylated cyanogenic glucosides based on prunasin, with six of these being new compounds, prunasin 2',6'-di-O-gallate (3), prunasin 3',6'-di-O-gallate (4), prunasin 4',6'-di-O-gallate (5), prunasin 2',3',6'-tri-O-gallate (6), prunasin 3',4',6'-tri-O-gallate (7), and prunasin 2',3',4',6'-tetra-O-gallate (8). Also obtained was a new alkyl glycoside, oct-1-en-3-yl alpha-arabinofuranosyl-(1-->6)-beta-glucopyranoside (9). For compounds 3-8, the galloyl groups were individually linked to the sugar moieties via ester bonds. All new structures were established on the basis of NMR and MS spectroscopic studies. In addition, prunasin (1), gallic acid and its methyl ester, beta-glucogallin, 3,6-di-O-galloyl-D-glucose, 1,2,3,6-tetra-O-galloyl-beta-D-glucose, strictinin, 6-O-galloyl-2,3-O-(S)-hexahydroxydiphenoyl-D-glucose, praecoxin B, and pterocarinin C were isolated and identified. The isolation of 1 and its galloyl derivatives (3-8) from a Melastomataceous plant are described for the first time.
authors.affiliation: Faculty of Pharmaceutical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: Sui-Kiong
authors.initials: SK
authors.lastname: Ling
authors.forename: Takashi
authors.initials: T
authors.lastname: Tanaka
authors.forename: Isao
authors.initials: I
authors.lastname: Kouno
mesh_terms: D000473:Alkanes / Q000737:chemistry / Q000302:isolation & purification; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification*; D008296:Malaysia; D013058:Mass Spectrometry; D015394:Molecular Structure; D009570:Nitriles / Q000737:chemistry / Q000302:isolation & purification; D019906:Nuclear Magnetic Resonance, Biomolecular; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D013634:Tannins / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000473:Alkanes; D006027:Glycosides; D009570:Nitriles; D013634:Tannins