Results 181 to 190 of about 1,268 (204)

Cytotoxic Prenylated Depsidones from Garcinia parvifolia

Journal of Natural Products, 2000
Leaf extracts of Garcinia parvifolia provided relatively high yields of four novel, cytotoxic prenylated depsidones. The structures were determined mainly by detailed NMR spectral analysis and X-ray crystallography.
Xu, Y.-J., Chiang, P.-Y., Lai, Y.-H., Vittal, J.J., Wu, X.-H., Tan, B.K.H., Imiyabir, Z., Goh, S.-H.   +7 more
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New Chlorine-Containing Depsidones From Lichens

Australian Journal of Chemistry, 1990
The depsidones, 3-O-demethylscensidin (2,7-dichloro-3-hydroxy-8-methoxy-1,6-dimethyl-11H-dibenzo[ b,e ][1,4]dioxepin-11-one)(5), O- methyldiploicin (2,4,7,9-tetrachloro-3,8-dimethoxy-1,6-dimethyl-11 H- dibenzo [ b,e ][1,4]dioxepin-11-one (6) and O- methylvicanicin (2,7-dichloro-3,8-dimethoxy-1,4,6,9-tetramethyl-11H-dibenzo[ b,e ][1,4]dioxepin-11-one ...
JA Elix, GA Jenkins, DA Venables
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Structure of the lichen depsidone pannarin

Journal of the Chemical Society, Chemical Communications, 1974
The published structure of pannarin{2-chloro-6-hydroxy-3-methoxy-1,4,8-trimethyl-11-oxo-11H-dibenzo[b,e]-[1,4]dioxepin-7-carbaldehyde}(1) is revised to 2-chloro-3-hydroxy-8-methoxy-1,6,9-trimethyl-11-oxo-11H-dibenzo[b,e][1,4]dioxepin-4-carbaldehyde (21), in the light of a combination of degradative, spectroscopic, and synthetic studies.
David A. Jackman, Melvyn V. Sargent, John A. Elix   +2 more
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ChemInform Abstract: DEPSIDONE SYNTHESIS. PART 11. SYNTHESIS OF SOME FUNGAL DEPSIDONES RELATED TO NIDULIN

Chemischer Informationsdienst, 1978
AbstractAusgehend von Oxo‐sulfon (Ia) wird sukzessiv über die angegebenen Stufen das Benzophenon (VIIb) synthetisiert, aus dem durch oxidative Kupplungsreaktion und nachfolgende Debromierung Tridechlordihydro‐nidulin (VIIIb) gewonnen wird.
P. DJURA, M. V. SARGENT
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Depsidone synthesis. VI. Colensoic acid

Australian Journal of Chemistry, 1976
The synthesis of the lichen depsidone colensoic acid (1) (8-hydroxy-3-methoxy-11-oxo-1,6-dipentyl- 11H-dibenzo[b,e][l,4]dioxepin-7-carboxylic acid) by Ullmann reaction of benzyl-2-bromo-4-methoxy- 6-pentylbenzoate (18) and methyl 4,6-dibenzyloxy-3-hydroxy-2-pentylbenzoate (27) and subsequent steps is described.
P Djura, MV Sargent
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Bioactive Depsidones from the Fungus Pilobolus heterosporus

Planta Medica, 2014
A new aromatic ester, pilobolusate (1), four new depsidones, pilobolusones A-D (2-5), five known depsidones, (6-10), and ergosterol were isolated from the fungus Pilobolus heterosporus. Their structures were established on the basis of spectroscopic data.
Oue-artorn, Rajachan, Somdej, Kanokmedhakul, Kwanjai, Kanokmedhakul, Kasem, Soytong   +3 more
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A new depsidone from Usnea diffracta

Chinese Chemical Letters, 2009
Abstract A new depsidone, diffractione A ( 1 ), as well as six known phenolic compounds ( 2 – 7 ) were isolated from Usnea diffracta . Their structures were elucidated by 1D and 2D NMR spectroscopy together with HRESIMS analysis. All components were obtained for the first time from U. diffracta.
Huan Yang Qi, Yuan Peng Jin, Yan Ping Shi   +2 more
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ChemInform Abstract: DEPSIDONE SYNTHESIS. IV. CALOPLOICIN

Chemischer Informationsdienst, 1976
AbstractNach Beschreibung eines ‐ wegen zu geringer Ausbeute bei einer Ullmann‐Reaktion ‐ erfolglosen Reaktionsweges zur Titelverbindung (Vb) wird diese wie folgt dargestellt: Rhizinonsäure (I) wird mit Surfurylchlorid in 5‐Stellung chloriert (73% Ausbeute), dibenzyliert und sofort die Benzylestergruppe zu (II) hydrolysiert (91%).
MELVYN V. SARGENT, PAUL VOGEL
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Structure of the lichen depsidone gangaleoidin

Journal of the Chemical Society, Perkin Transactions 1, 1975
As a result of degradative, spectroscopic, and synthetic evidence the structure of the lichen depsidone gangaleoidin is revised to methyl 2,4-dichloro-3-hydroxy-8-methoxy-1,6-dimethyl-11-oxo-11H-dibenzo [b,e][1,4]dioxepin-7-carboxylate. Gangaleoidin was degraded to methyl 3-(2-methoxycarbonyl-5-methoxy-3-methylphenoxy)-4,6-dimethoxy-2-methylbenzoate ...
Melvyn V. Sargent, Paul Vogel, John A. Elix   +2 more
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Depsidone synthesis. VII. Vicanicin and norvicanicin

Australian Journal of Chemistry, 1976
The lichen Psoroma sphinctrinurn (Mont.) Nyl. occurs in two or more chemical strains. 2,7-Dichloro- 3 - hydroxy -8-methoxy- 1,4,6,9 - tetramethyl - 11H- dibenzo[b,e][l,4]dioxepin- 11-one (vicanicin) (2), a known depsidone, is a metabolite of one strain, and 2,7-dichloro-3,8-dihydroxy-1,4,6,9-tetramethyl-1lH-dibenzo[b,e][1,4]dioxepin-11-one ...
MV Sargent, P Vogel, JA Elix, BA Ferguson   +3 more
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