Results 171 to 180 of about 46,318 (209)
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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
exaly +3 more sources
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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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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Planta Medica, 1994
Five xanthones have been isolated from Garcinia cowa Roxb. (Guttiferae): cowanin (1), cowanol (2), cowaxanthone (3), 1,3,6-trihydroxy-7-methoxy- 2-5-bis(3-methyl-2-butenyl)xanthone (4), and norcowanin (5). The structures were assigned by spectroscopic studies. Xanthones 2 and 3 showed moderate antimicrobial activity against Staphylococcus aureus.
P, na Pattalung +3 more
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Five xanthones have been isolated from Garcinia cowa Roxb. (Guttiferae): cowanin (1), cowanol (2), cowaxanthone (3), 1,3,6-trihydroxy-7-methoxy- 2-5-bis(3-methyl-2-butenyl)xanthone (4), and norcowanin (5). The structures were assigned by spectroscopic studies. Xanthones 2 and 3 showed moderate antimicrobial activity against Staphylococcus aureus.
P, na Pattalung +3 more
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The binding of xanthone derivatives to transthyretin
Biochemical Pharmacology, 2005A series of xanthone derivatives, isolated from Calophyllum teysmannii var. inophylloide, have been evaluated for their binding affinity to transthyretin. Transthyretin is a plasma protein involved in the transport of thyroxine (T4) and also implicated in amyloid diseases.
Filipe, Maia +6 more
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Sulfonated Xanthones from Hypericum sampsonii.
ChemInform, 2004Xanthones, 1,3-dihydroxy-5-methoxyxanthone-4-sulfonate and 1,3-dihydroxy-5-O-beta-D-glycopyranosylxanthone-4-sulfonate, together with nine known compounds were obtained from H. sampsonii. This is the first report of sulfonated xanthonoids. Furthermore, compounds 1 and 2 exhibited significant cytotoxicity against the P388 cancer cell line.
Di, Hong +3 more
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Xanthones as systematic markers
Biochemical Systematics and Ecology, 1973Abstract An evolutionary scheme for shikimate-acetate derived xanthones is deduced from their substitution pattern. Increasing distance of a particular xanthone from the primitive precursor is symbolized by increasing numbers. Each xanthone containing plant species is characterized by the average of the numbers attributed to its constituents.
Ceres Maria Andrade da Mata Rezende +1 more
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Xanthones of Rheedia gardneriana
Phytochemistry, 1970Abstract 1,5-Dihydroxyxanthone, 1,7-dihydroxyxanthone, 1,6-dihydroxy-5-methoxyxanthone, lupeol, betulin and β-sitosterol were isolated from Rheedia gardneriana Pl. & Tr.
R.Braz Filho +2 more
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