title: Lanostanes and friedolanostanes from the bark of Garcinia speciosa.
abstract: The CHCl(3) extract of the bark of Garcinia speciosa contained four 17,14-friedolanostanes and five lanostanes as well as friedelin and common plant constituents. The friedolanostanes were the previously known methyl ester of (24E)-3 alpha,23 alpha-dihydroxy-17,14-friedolanostan-8,14,24-trien-26-oic acid and the methyl esters of three hitherto unknown acids, 3 alpha-hydroxy-16 alpha,23 alpha-epoxy-17,14-friedolanostan-8,14,24-trien-26-oic acid, 3 alpha,23 alpha-dihydroxy-8 alpha,9 alpha-epoxy-17,14-friedolanostan-15-oxo-24-en-26-oic acid and 3 alpha,23 alpha-dihydroxy-17,14-friedolanostan-15-oxo-8(14),24-dien-26-oic acid. New lanostanes were 3 beta,9 alpha-dihydroxylanost-24-en-26-al and the methyl ester of 3 beta-hydroxy-23-oxo-9,16-lanostadien-26-oic acid. Structures were established by analysis of spectroscopic data. In the case of the lanostanes the previously unassigned C-25 stereochemistry was shown to be 25R by X-ray analysis of 3 beta-hydroxy-23-oxo-9,16-lanostadien-26-oic acid. In the case of the friedolanostanes the configuration at C-23 was established as 23R, identical with the absolute configuration at C-23 of mariesiic acids A and B.
authors.affiliation: Departamento de Química, Universidade de Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Luis M M
authors.initials: LM
authors.lastname: Vieira
authors.forename: Anake
authors.initials: A
authors.lastname: Kijjoa
authors.forename: Artur M S
authors.initials: AM
authors.lastname: Silva
authors.forename: Ing-On
authors.initials: IO
authors.lastname: Mondranondra
authors.forename: Surapong
authors.initials: S
authors.lastname: Kengthong
authors.forename: Luis
authors.initials: L
authors.lastname: Gales
authors.forename: Ana Margarida
authors.initials: AM
authors.lastname: Damas
authors.forename: Werner
authors.initials: W
authors.lastname: Herz
mesh_terms: D029760:Garcinia / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D024301:Plant Bark / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification; D014961:X-Ray Diffraction
chemical_list: D010936:Plant Extracts; D014315:Triterpenes