title: Two xanthones from Polygala paniculata and confirmation of the 1-hydroxy-2,3,5-trimethoxy-xanthone at trace level by HRGC-MS.
abstract: Polygala paniculata L. yielded the xanthones 1-hydroxy-5-methoxy-2,3-methylenedioxyxanthone (1) and 1,5-dihydroxy-2,3-dimethoxyxanthone (2), together with coumarin murragatin and flavonol rutin. Their structures were established by chemical and spectroscopic methods (EIMS, IR, 1H and 13C NMR, NOE difference spectroscopy). By posterior analysis of an apolar crude extract using high resolution gas chromatography coupled to mass spectrometry (HRGC-MS) it was possible to characterize two sterol (spinasterol and delta25-spinasterol) and the minor 1-hydroxy-2,3,5-trimethoxyxanthone (3). Thus, the xanthone 3 was confirmed through of co-injection HRGC-MS of the respective extract with a certified standard obtained by methylation of 2 with diazomethane.
authors.affiliation: Departamento de Química, Universidade Federal de Santa Catarina, 98010-970 Florianópolis, SC, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Cristiano
authors.forename: Moacir G
authors.initials: MG
authors.lastname: Pizzolatti
authors.forename: Franco
authors.initials: F
authors.lastname: Delle Monache
authors.forename: Claudia M
authors.initials: CM
authors.lastname: Rezende
authors.forename: Alexsandro
authors.initials: A
authors.lastname: Branco
mesh_terms: D002849:Chromatography, Gas; D008401:Gas Chromatography-Mass Spectrometry; D008958:Models, Molecular; D015394:Molecular Structure; D035261:Plant Components, Aerial / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification; D031801:Polygala / Q000737:chemistry*; D014966:Xanthenes / Q000737:chemistry* / Q000302:isolation & purification; D044004:Xanthones
chemical_list: C478004:1-hydroxy-2,3,5-trimethoxyxanthone; D010936:Plant Extracts; D014966:Xanthenes; D044004:Xanthones; C009689:xanthone