Results 171 to 180 of about 7,063 (213)
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Secoiridoids and Xanthones in the Genus Centaurium
Planta Medica, 1981Overground parts of Centaurium spicatum (L.) Fritsch (Gentianaceae) from two different habitats have been investigated on their content of Secoiridoid glucosides. Sweroside (I), Swertiamarin (II) and gentiopicrin (III) (= gentiopicroside) have been identified. In plant material of C. spicatum from both habitats sweroside is the major compound. In plant
W G, van der Sluis, R P, Labadie
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A New Regiospecific Preparation of Xanthones
Organic Letters, 2003AbstractFor Abstract see ChemInform Abstract in Full Text.
Frank M, Hauser, Warren A, Dorsch
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Acta Crystallographica Section C Crystal Structure Communications, 1990
C 13 H 8 O 2 cristallise dans P2 1 2 1 2 1 avec a=14,072, b=13,627, c=4,878A, Z=4 ; affinement jusqu'a R=0,077. La molecule est plane sauf pour l'atome O du carbonyl (0,13A hors du plan). Les cycles benzene ne sont pas des hexagones reguliers mais la distorsion est symetrique et la molecule a la symetrie C 2v approximative. Il n'y a pas de distances
S. Onuma, K. Iijima, I. Oonishi
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C 13 H 8 O 2 cristallise dans P2 1 2 1 2 1 avec a=14,072, b=13,627, c=4,878A, Z=4 ; affinement jusqu'a R=0,077. La molecule est plane sauf pour l'atome O du carbonyl (0,13A hors du plan). Les cycles benzene ne sont pas des hexagones reguliers mais la distorsion est symetrique et la molecule a la symetrie C 2v approximative. Il n'y a pas de distances
S. Onuma, K. Iijima, I. Oonishi
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Metabolism of Xanthone in the Rat
Xenobiotica, 1974Abstract1. The metabolism of xanthone by the rat has been investigated.2. The major unconjugated urinary metabolite was 4-hydroxyxanthone (24%). Smaller amounts of free 2-hydroxyxanthone (13%) and 3-hydroxy-xanthone (6%) were also formed. Other fluorescent metabolites were detected in trace amounts.3.
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Xanthones from Swertia punctata
Phytochemistry, 2002Isolation of 1-O-primeverosyl-3,8-dihydroxy-5-methoxyxanthone and 1-O-gentiobiosyl-3,7-dimethoxy-8-hydroxyxanthone, along with five known xanthones, isobellidifolin, methylbellidifolin, isoswertianin, methylswertianin and norswertianin-1-O-beta-D-glucoside, from the roots of Swertia punctata is reported. In the aerial parts four xanthones, bellidifolin,
Menkovic, N +7 more
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Microwave‐Assisted Xanthone Synthesis
Synthetic Communications, 2006AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
E. A. Evangelista +4 more
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A xanthone from Shultesia guianensis
Fitoterapia, 2001The isolation of 1-hydroxy-3,7-dimethoxyxanthone (1) from Shultesia guianensis is reported along with relevant NMR spectra, including new data by two-dimensional NMR experiments (HMQC and HMBC).
F J, Monte, F P, Soares, R, Braz-Filho
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Xanthones from Hypericum chinense
Phytochemistry, 2006Six xanthones, 1,3,7-trihydroxy-2-(2-hydroxy-3-methyl-3-butenyl)-xanthone (1), 1,7-dihydroxy-2,3-[2''-(1-hydroxy-1-methylethyl)-dihydrofurano]-xanthone (2), 1,3,7-trihydroxy-5-methoxyxanthone (3), 1,7-dihydroxy-5,6-dimethoxyxanthone (4), 4,5-dihydroxy-2,3-dimethoxyxanthone (5), 1,3-dihydroxy-2,4-dimethoxyxanthone (6) and 21 known xanthones were ...
Naonobu, Tanaka, Yoshihisa, Takaishi
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Xanthones from Hypericum roeperanum
Phytochemistry, 1996Four new xanthones have been isolated from the roots of Hypericum roeperanum. Their structures have been established by a combination of spectroscopic and chemical methods as 1,6-dihydroxy-5-methoxy-4',5'-dihydro-4',4',5'-trimethylfurano- (2',3':3,4)-xanthone (5-O-methyl-2-deprenylrheediaxanthone B), 1,6-dihydroxy-5-methoxy-6',6'-dimethylpyrano-(2',3 ...
Rath G +3 more
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