Cytotoxic prenylxanthones from Garcinia bracteata.
Bioassay-guided fractionation of a leaf extract of G. bracteata has yielded six new prenylxanthones, bractatin (1), isobractatin (2), 1-O-methylbractatin (3), 1-O-methylisobractatin (4), 1-O-methyl-8-methoxy-8,8a-dihydrobractatin (5), and 1-O-methylneobractatin (6). The structures of these compounds have been elucidated by spectroscopic means (NMR, MS), literature data, and X-ray crystallographic analysis of 2. These compounds possess significant cytotoxicity against the KB cell line.
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Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, 91198 Gif-sur-Yvette Cedex, France.
Fahy
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J
Dumontet
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V
Chiaroni
A
A
Riche
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Tri
M V
MV
Sévenet
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T
D019883:Alkyl and Aryl Transferases / Q000037:antagonists & inhibitors; D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification* / Q000494:pharmacology; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D007624:KB Cells; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D014966:Xanthenes / Q000302:isolation & purification* / Q000494:pharmacology
D000972:Antineoplastic Agents, Phytogenic; D004791:Enzyme Inhibitors; D014966:Xanthenes; D019883:Alkyl and Aryl Transferases; C064911:p21(ras) farnesyl-protein transferase