Results 191 to 200 of about 1,764 (217)

Depsidone synthesis. Part 16. Benzophenone–grisa-3′,5′-diene-2′,3-dione–depsidone interconversion: a new theory of depsidone biosynthesis

J. Chem. Soc., Perkin Trans. 1, 1981
The synthesis of a number of grisa-3′,5′-diene-2′,3-diones by oxidative coupling of substituted 2,2′-dihydroxy-4-methoxybenzophenones is described. The rearrangement of these grisadienediones to depsidones under basic, acidic, and thermal conditions is described and the mechanisms of these reactions are discussed.
Tony Sala, Melvyn V. Sargent
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Depsidones from the Endophytic Fungus BCC 8616

Journal of Natural Products, 2006
Three new depsidones (1-3) have been isolated from the endophytic fungus BCC 8616 and their structures analyzed on the basis of spectroscopic data interpretation. Compound 1 exhibited weak cytotoxic activity against breast and epidermoid carcinoma cell lines.
Pattama, Pittayakhajonwut, Aibrohim, Dramae, Siribhorn, Madla, Nattapat, Lartpornmatulee, Nattawut, Boonyuen, Morakot, Tanticharoen   +5 more
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New depsidones from Lobaria oregana

Phytochemistry, 1980
Abstract From the lichen, Lobaria oregana , two new minor metabolises, methylstictic acid ( 4 ) and cryptostictic acid ( 5 ) were isolated. The structures of 4 and 5 were elucidated by 1 H NMR and MS analysis.
Sachiko Shimada (née Miyoshi), Tamotsu Saitoh, Ushio Sankawa, Shoji Shibata   +3 more
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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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