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Registros recuperados: 6
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Steroidal glycosides from the marine sponge Pandaros acanthifolium OceanDocs
Cachet, N.; Regalado, E.L.; Genta-Jouve, G.; Mehiri, M.; Amade, P.; Thomas, O.P..
The chemical composition of the Caribbean sponge Pandaros sp. was investigated and led to the isolation of seven new steroidal glycosides namely pandarosides A-D (1, 3, 4 and 6) along with the three methyl esters of pandarosides A, C, and D (2, 5 and 7). Their structures were characterized as 3β-[β-glucopyranosyl-(1→2)-β-glucopyranosyloxyuronic acid]-16-hydroxy- 5α,14β-poriferast-16-ene-15,23-dione (1) and its methyl ester (2), 3β-[β- glucopyranosyloxyuronic acid]-16-hydroxy-5α,14β-poriferast-16-ene-15,23-dione (3), 3β-[β- glucopyranosyl-(1→2)-β-glucopyranosyloxyuronic acid]-16-hydroxy-5α,14β-cholest-16-ene- 15,23-dione (4) and its methyl ester (5), 3β-(β-glucopyranosyloxyuronic acid)-16-hydroxy- 5α,14β-cholest-16-ene-15,23-dione (6) and its methyl ester...
Tipo: Journal Contribution Palavras-chave: Sponges; Sponges; Http://aims.fao.org/aos/agrovoc/c_7321.
Ano: 2009 URL: http://hdl.handle.net/1834/3859
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Bromopyrrole alkaloids from the Caribbean sponge Agelas cerebrum OceanDocs
Regalado, E.L.; Laguna, A.; Mendiola, J.; Thomas, O.P.; Nogueiras, C..
Bioguided fractionation of Agelas cerebrum crude extract resulted in isolation of four bromopyrrole and four bromopyrrole aminoimidazole alkaloids, identified as 5-bromopyrrole-2-carboxylic acid (1), 4-bromopyrrole-2-carboxylic acid (2), 3,4-bromopyrrole-2-carboxylic acid (3), 4,5-bromopyrrole-2-carboxylic acid (4), oroidin (5), bromoageliferin (6), dibromoageliferin (7) and dibromosceptrin (8) on the basis of spectroscopic data analyses (UV, IR, HRMS, 1D and 2D NMR) and comparison with literature data. This is the first report of compounds 2 and 3 in a marine sponge belonging to the Agelas genus and the first evidence of the presence of 1 from a natural source.
Tipo: Journal Contribution Palavras-chave: Alkaloids; Sponges; Chemistry; Chemistry; Alkaloids; Sponges; Http://aims.fao.org/aos/agrovoc/c_1522; Http://aims.fao.org/aos/agrovoc/c_269; Http://aims.fao.org/aos/agrovoc/c_7321.
Ano: 2010 URL: http://hdl.handle.net/1834/3862
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Acanthifoliosides, minor steroidal saponins from the Caribbean marine sponge Pandaros acanthifolium OceanDocs
Regalado, E.L.; Jiménez-Romero, C.; Genta-Jouve, G.; Tasdemir, D.; Amade, P.; Nogueiras, C.; Thomas, O.P..
Seven novel steroid glycosides, acanthifoliosides A-F (1-6) and the methyl ester of 6 (7), were isolated from the marine sponge Pandaros acanthifolium as minor components. Acanthifoliosides are characterized by a rare C-15 and C-16 oxidized D ring which was previously found in saponins produced by starfishes. Very uncommon is the presence of additional sugar residues at C-15 or C-16. Their structures were determined on the basis of extensive spectroscopic analyses, including two-dimensional NMR and HRESIMS data. The absolute configurations of the aglycones were assigned by comparison between experimental and TDDFT calculated CD spectra of 1, whereas the absolute configurations of the monosaccharide units were determined by chiral GC analyses of the acid...
Tipo: Journal Contribution Palavras-chave: Sponges; Sponges; Http://aims.fao.org/aos/agrovoc/c_7321.
Ano: 2011 URL: http://hdl.handle.net/1834/3866
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Polar Alkaloids from the Caribbean Marine Sponge Niphates digitalis OceanDocs
Regalado, E.L.; Mendiola, J.; Laguna, A.; Nogueiras, C.; Thomas, O.P..
A method involving flash chromatography, semi-preparative phenylhexyl RP HPLC-DAD-ELSD combined with analytic polar-RP HPLC-DAD, was applied to separate and purify six highly nitrogenated bases and a bicyclic amidine alkaloid, the major components of the marine sponge Niphates digitalis. Their structures were identified as 1,8-diazabicyclo[5.4.0]undec-7- ene (1), deoxycytidine (2), phenylalanine (3), adenosine (4), deoxyguanosine (5), adenine (6) and thymidine (7) on the basis of spectroscopic data analyses. This is the first report of these compounds in a marine sponge belonging to the Niphates genus and the first evidence of the presence of 1 from a natural source.
Tipo: Journal Contribution Palavras-chave: Sponges; Cytotoxicity; Cytotoxicity; Sponges; Http://aims.fao.org/aos/agrovoc/c_34251; Http://aims.fao.org/aos/agrovoc/c_7321.
Ano: 2010 URL: http://hdl.handle.net/1834/3860
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Parazoanthines A-E: Hydantoin Alkaloids from the Mediterranean Sea Anemone Parazoanthus axinellae OceanDocs
Cachet, N.; Genta-Jouve, G.; Regalado, E.L.; Mokrini, R.; Amade, P.; Culioli, G.; Thomas, O.P..
Five new hydantoin alkaloids, named parazoanthines A-E (1-5), were isolated as the major constituents of the Mediterranean sea anemone Parazoanthus axinellae. Their structural elucidation was achieved through NMR spectroscopic and mass spectrometric analyses. The absolute configuration of the chiral compounds 1 and 4 was determined by comparison between experimental and TDDFT calculated CD spectra. The configuration of the trisubstituted double bond of 2, 3, and 5 was deduced from the 3JH6-C4 coupling constant value. This family of alkaloids represents the first example of natural 3,5- disubstituted hydantoins which do not exhibit a methyl at N-3. All compounds were tested for their natural toxicity (Microtox® assay) and parazoanthine C (3) exhibited the...
Tipo: Journal Contribution Palavras-chave: Alkaloids; Alkaloids; Http://aims.fao.org/aos/agrovoc/c_269.
Ano: 2009 URL: http://hdl.handle.net/1834/3864
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Antiprotozoal steroidal saponins from the marine sponge Pandaros acanthifolium OceanDocs
Regalado, E.L.; Tasdemir, D.; Kaiser, M.; Cachet, N.; Amade, P.; Thomas, O.P..
The chemical composition of the Caribbean sponge Pandaros acanthifolium was reinvestigated and led to the isolation of 12 new steroidal glycosides, namely, pandarosides E-J (1-6) and their methyl esters (7-12). Their structures were determined on the basis of extensive spectroscopic analyses, including two-dimensional NMR and HRESIMS data. Like the previously isolated pandarosides A-D (13-16), the new compounds 1-12 share an unusual oxidized D-ring and a cis C/D ring junction. The absolute configurations of the aglycones were assigned by interpretation of CD spectra, whereas the absolute configurations of the monosaccharide units were determined by chiral GC analyses of the acid methanolysates. The majority of the metabolites showed in Vitro activity...
Tipo: Journal Contribution Palavras-chave: Sponges; Sponges; Http://aims.fao.org/aos/agrovoc/c_7321.
Ano: 2010 URL: http://hdl.handle.net/1834/3863
Registros recuperados: 6
Primeira ... 1 ... Última
 

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