Results 161 to 170 of about 1,421 (204)

Depsidone synthesis. IV. Caloploicin

Australian Journal of Chemistry, 1976
The synthesis of the lichen depsidone caloploicin (2,4,7-trichloro-3-hydroxy-8-methoxy-1,6,9- trimethyldibenzo[b,e][l,4]dioxepin-11-one) (1) by oxidative coupling of 5'-chloro-2,2',4-trihydroxy-4- methoxy-3',6,6'-trimethylbenzophenone (23), and subsequent steps, is described.
MV Sargent, P Vogel
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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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Three New Lichen Depsidones

Australian Journal of Chemistry, 1987
The depsidones a- acetylconstictic acid (5-acetoxymethyl-1,4-dihydroxy-10-methoxy-8-methyl-3,7-dioxo-1,3-dihydro-7 H- isobenzofuro [4,5- b][l,4] benzodioxepin-ll-carbaldehyde ) (6), substictic acid (1,4-dihydroxy-10-methoxy-8-methy1-3,7-dioxo- 1,3-dihydro-7 H- isobenzofuro [4,5-b][1,4]benzodioxepin-11-carbaldehyde) (7) and conphysodalic acid (9 ...
JA Elix, KL Gaul, PW James, OW Purvis
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ChemInform Abstract: DEPSIDONE SYNTHESIS. PART 16. BENZOPHENONE‐GRISA‐3′,5′‐DIENE‐2′,3‐DIONE‐DEPSIDONE INTERCONVERSION: A NEW THEORY OF DEPSIDONE BIOSYNTHESIS

Chemischer Informationsdienst, 1981
AbstractOxidative Kupplung der substituierten 2,2′‐Dihydroxy‐4‐methoxy‐benzophenone (I), (IV) bzw. (VII) mit K3 [Fe(CN)6] unter optimalen Bedingungen liefert die Grisadiendione (II), (V) bzw. (VIII), die sich bei Thermolyse in fester Form oder in Lösungsmitteln wie TFA/ CHz C12, Diphenylether oder Phenetol in die Depsidone (III), (VI) bzw.
T. SALA, M. V. SARGENT
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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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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. III. Grayanic acid

Australian Journal of Chemistry, 1976
The structure of the lichen depsidone grayanic acid (1) (6-heptyl-8-hydroxy-3-methoxy-1-methyl-11- oxo-11 H -dibenzo[b,e][1,4]dioxepin-7-carboxylic acid) proposed by Shibata and Chiang was confirmed by the synthesis firstly of methyl O -methylgrayanate (19), and then of grayanic acid itself. The key step in both syntheses was an Ullmann reaction.
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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Depsidones and fatty acids of Parmelia stygia

Phytochemistry, 1984
Abstract One Russian sample of the lichen Parmelia stygia has yielded fumarprotocetraric acid, while a second contained the same compound accompanied by colensoinic, lobaric, caperatic and norcaperatic acids.
Nataliya P. Mishchenko, Oleg B. Maximov, Olga E. Krivoshchekova, Ljudmila S. Stepanenko   +3 more
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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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