- Identification and total synthesis of novel fatty acids from the caribbean sponge Calyx podatypa
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The phospholipid fatty acid composition of the Caribbean sponge Calyx podatypa was studied, and 85 different fatty acids were identified, in particular the 11-methylpentadecanoic acid and 10-tricosenoic acid, which have no literature precedence. Structural characterization was accomplished by means of gas chromatography - mass spectrometry on their corresponding methyl esters and dimethyl disulfide derivatives. The structure of 11- methylpentadecanoic acid was further confirmed by total synthesis (17% overall yield) starting from commercially available 10-hydroxydecanoic acid.
- Carballeira, Nestor M.,Pagan, Mayra,Rodriguez, Abimael D.
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- Oceanapins A-F, unique branched ceramides isolated from the haplosclerid sponge Oceanapia cf. tenuis of the Coral Sea
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A series of ceramides, called oceanapins A-F, which are unique for branching at both the sphingosine and fatty-acid chains, have been isolated as pure compounds from the haplosclerid sponge Oceanapia cf. tenuis of the Coral Sea. Following acid hydrolysis, both the fatty-acid and the sphingosine portions were obtained separately, which allowed their unequivocal structural definition. The absolute configuration was secured via protection of C(l')-OH and Mosher's esterification at C(3')-OH of the oceanapins.
- Mancini,Guella,Debitus,Pietra
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- Dammarane triterpenoids from Carnauba, Copernicia prunifera (Miller) H. E. Moore (Arecaceae), wax
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Phytochemical investigation from carnauba (Copernicia prunifera) wax led to the identification of sixteen dammarane–type triterpenes, including thirteen new characterized as: (24R*)-methyldammara-20,25-dien-3α-ol and a mixture of alkyl (24R*)-methyldammar-25-en-20-ol-3β-carboxylates, together with three previously described triterpenes: carnaubadiol, (24R*)-methyldammara-20,25-dien-3β-ol and (24R*)-24-methyldammara-20,25-dien-3-one. Moreover, four fatty alcohols (eicosanol, docosanol, tetracosanol and hexacosanol) as well as four sterols (cholesterol, campesterol, stigmasterol, and sitosterol) were also obtained. These compounds were isolated using classical chromatographic methods and their structures were determined by spectroscopic and chemical methods.
- De Almeida, Buana C.,Araújo, Bruno Q.,Barros, Elcio D. S.,Freitas, Samya D. L.,Maciel, Dayany S. A.,Ferreira, Ari J. S.,Guadagnin, Rafael C.,Vieira, Gerardo M.,Lago, Jo?o H. G.,Chaves, Mariana H.
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p. 1371 - 1376
(2017/07/13)
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- A New Synthesis of Long Chain Acid Esters and Carbinols
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A versatile synthesis of difficulty accessible long chain acid esters and carbinols is described.The synthesis involves acylations at 2- and 5-positions of thiophene.Thioketalation of the resulting ketoesters followed by Raney nickel desulfurization yield acid esters which on LAH reduction give the corresponding carbinols.
- Rao, S. Jagadishwar,Bhalerao, U. T.,Tilak, B. D.
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p. 208 - 211
(2007/10/02)
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