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Search Results: 1 - 10 of 155096 matches for " Magalh?es Aderbal F. "
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New spectral data of some flavonoids from Deguelia hatschbachii A.M.G. Azevedo
Magalhes, Aderbal F.;Tozzi, Ana M. G. A.;Magalhes, Eva G.;Moraes, Valéria R. de S.;
Journal of the Brazilian Chemical Society , 2003, DOI: 10.1590/S0103-50532003000100022
Abstract: from the roots of deguelia hatschbachii, the known flavonoids scandenin (1), methyl robustate (2) and 4',5- dihydroxy-6-(3,3-dimethylalyll)-7-methoxy flavanone (3) were isolated and characterized by comparison of their spectroscopic data with those found in the literature. now the inclusion of 1d- and 2d-nmr and ms/ms data has allowed the complete assignment of all hydrogen and carbon chemical shifts in their nmr spectra, as well as the elucidation of the fragmentation pathways of 1-3 in the mass spectrometer.
Flavonoids from Lonchocarpus muehlbergianus
Magalhes Aderbal F.,Tozzi Ana M.G.A.,Magalhes Eva G.,Blanco Ivani S.
Anais da Academia Brasileira de Ciências , 2004,
Abstract: The light petroleum extract from the roots of Lonchocarpus muehlbergianus Hassl contained nine flavonoids, including six new ones. These are 2,4-cis-2,4,5,8-tetramethoxy-(2,3:6,7)-furanoflavan; 2,4-cis-4-hydroxy-2,5,8-trimethoxy-(2,3:6,7)-furanoflavan; 2,4-cis-2-prenyloxy-4,5,8-trimethoxy-(2,3:6,7)-fu-ranoflavan; 2,4-cis-2-prenyloxy-4-hydroxy-5,8-dimethoxy-(2,3:6,7)-furanoflavan; 2',5',6'-trimethoxy-9-(1,1-dimethylallyoxy)-[2,3:3,4]-furanochalcone; 5,6-dimethoxy-(2,3:7,8)-furanoflavone, identi-fied by analysis of their spectral data (UV, IR, 1H and 13C NMR, 2D-NMR, NOE and MS). The natural occurrence of 2,4-dioxygenated flavan derivatives is being reported for the first time. Quantitative analysis of the petrol extract, by using reversed-phase HPLC, showed that the most abundant flavonoid in the extract is 2,4-cis-2,4,5,8- tetramethoxy-(2,3:6,7)-furanoflavan.
New spectral data of some flavonoids from Deguelia hatschbachii A.M.G. Azevedo
Magalhes Aderbal F.,Tozzi Ana M. G. A.,Magalhes Eva G.,Moraes Valéria R. de S.
Journal of the Brazilian Chemical Society , 2003,
Abstract: From the roots of Deguelia hatschbachii, the known flavonoids scandenin (1), methyl robustate (2) and 4',5- dihydroxy-6-(3,3-dimethylalyll)-7-methoxy flavanone (3) were isolated and characterized by comparison of their spectroscopic data with those found in the literature. Now the inclusion of 1D- and 2D-NMR and MS/MS data has allowed the complete assignment of all hydrogen and carbon chemical shifts in their NMR spectra, as well as the elucidation of the fragmentation pathways of 1-3 in the mass spectrometer.
Flavonoids of Lonchocarpus montanus A.M.G. Azevedo and biological activity
Magalhes, Aderbal F.;Tozzi, Ana Maria G.A.;Magalhes, Eva G.;Sannomiya, Miriam;Soriano, Maria del Pilar C.;Perez, Mary A.F.;
Anais da Academia Brasileira de Ciências , 2007, DOI: 10.1590/S0001-37652007000300001
Abstract: the analysis of root extracts from lonchocarpus montanus a.m.g. azevedo resulted in the isolation of twenty three compounds chiefly flavonoids of which five (four flavonoids and one benzophenone) are described for the first time. the molecular structures of the new compounds (1-5) were determined through spectral analysis (uv, ir, ms and nmr) as being: 2'-hydroxy-8-(a,a-dimethylallyl)-2", 2"-dimethylpyrano-(5",6":3',4')-dibenzoylmethane (1), 2'-methoxy-8-(a, a-dimethylallyl)-2", 2"-dimethylpyrano-(5",6":3',4')-dibenzoylmethane (2), 4'-methoxy-2",2"-dimethylpyrano-(5",6":8,7)-flavone (3), 2"-(1-hydroxy-1-methylethyl)-furano-(4",5":8,7)-flavone (4) and [2'-methoxy-furano-(4",5":3',4')-phenyl]-phenylmethanone (5). additionally, fifteen fatty acids were detected through gc-ms analysis of the corresponding methyl esters [(ch3)2ch(ch2)8cooh and ch3(ch2)ncooh (n = 6, 12-24)]. quantitative rp-hplc showed that the most abundant flavonoids in the petroleum ether and dichloromethane extracts were pongamol (19%) and lanceolatine b (8.0%), respectively. in the bioautography assay, the extracts, pongamol (9), lanceolatine b (10), isolonchocarpin (14), derriobtusone a (17) and medicarpine (18) were active against staphilococus aureus whereas 9 also against bacillus subtilis and cladosporium cladosporioides. compound 1, 2",2"-dimethylpyrano-(5",6":8,7)-flavone (11) and furano-(1200,1300:7,8)- 4'-methoxy flavone (12) were active against fusarium oxysporium whereas 11 also against rhizopus orizae. the extracts, compounds 9, 10, 17 and (e)-7-o-methoxypongamol (23) displayed high toxicity in the brine shrimp lethality assay.
New hopane triterpene from Eleocharis sellowiana (Cyperaceae)
Ruiz, Ana Lúcia T. G.;Magalhes, Aderbal F.;Faria, Aparecida D.;Magalhes, Eva G.;Amaral, Maria do Carmo E.;
Journal of the Brazilian Chemical Society , 2006, DOI: 10.1590/S0103-50532006000400025
Abstract: a new triterpene named 3a-hydroxy-13a,17a,21b-hopan-15,19-dione and e-phytyl hexadecanoate were isolated from the hexanic extract of eleocharis sellowiana. nmr and ms experiments determined the molecular structures.
Flavonoids from Lonchocarpus muehlbergianus
Magalhes, Aderbal F.;Tozzi, Ana M.G.A.;Magalhes, Eva G.;Blanco, Ivani S.;Soriano, Maria-Del-Pilar C.;
Anais da Academia Brasileira de Ciências , 2004, DOI: 10.1590/S0001-37652004000400004
Abstract: the light petroleum extract from the roots of lonchocarpus muehlbergianus hassl contained nine flavonoids, including six new ones. these are 2,4-cis-2,4,5,8-tetramethoxy-(2′′,3′′:6,7)-furanoflavan; 2,4-cis-4-hydroxy-2,5,8-trimethoxy-(2′′,3′′:6,7)-furanoflavan; 2,4-cis-2-prenyloxy-4,5,8-trimethoxy-(2′′,3′′:6,7)-fu-ranoflavan; 2,4-cis-2-prenyloxy-4-hydroxy-5,8-dimethoxy-(2′′,3′′:6,7)-furanoflavan; 2',5',6'-trimethoxy-9-(1,1-dimethylallyoxy)-[2′′,3′′:3′,4′]-furanochalcone; 5,6-dimethoxy-(2′′,3′′:7,8)-furanoflavone, identi-fied by analysis of their spectral data (uv, ir, 1h and 13c nmr, 2d-nmr, noe and ms). the natural occurrence of 2,4-dioxygenated flavan derivatives is being reported for the first time. quantitative analysis of the petrol extract, by using reversed-phase hplc, showed that the most abundant flavonoid in the extract is 2,4-cis-2,4,5,8- tetramethoxy-(2′′,3′′:6,7)-furanoflavan.
Enzymatic inhibition studies of selected flavonoids and chemosystematic significance of polymethoxylated flavonoids and quinoline alkaloids in Neoraputia (Rutaceae)
Moraes, Valéria R. de S.;Tomazela, Daniela M.;Ferracin, Ricardo J.;Garcia, Cleverson F.;Sannomiya, Míriam;Soriano, M. del Pilar C.;Silva, M. Fátima das G. F. da;Vieira, Paulo C.;Fernandes, Jo?o B.;Rodrigues Filho, Edson;Magalhes, Eva G.;Magalhes, Aderbal F.;Pimenta, Eli F.;Souza, Dulce H. F. de;Oliva, Glaucius;
Journal of the Brazilian Chemical Society , 2003, DOI: 10.1590/S0103-50532003000300007
Abstract: our taxonomic interest in the neoraputia stimulated an investigation of n. paraensis searching for alkaloids. fractions were monitored by 1h nmr and esi-ms/ms and only those which showed features of anthranilate alkaloids and flavonoids absent in the previous investigations were examined. stems afforded the alkaloids flindersine, skimmianine, 8-methoxyflindersine and dictamnine; leaves yielded 3',4',7,8-tetramethoxy-5,6-(2",2"-dimethylpyrano)-flavone, 3',4',5,7,8-pentamethoxyflavone, 5-hydroxy-3',4',6,7-tetramethoxyflavone, 3',4'-methylenedioxy-5,6,7-trimethoxyflavone and 5-hydroxy-3',4'-methylenedioxy-6,7-dimethoxyflavone. the alkaloids have remained undiscovered for 10 years. a number of flavonoids isolated from n. paraensis, n. magnifica, murraya paniculata, citrus sinensis graft (rutaceae), lonchocarpus montanus (leguminosae) were evaluated for their ability to inhibit the enzymatic activity of the protein glyceraldehyde-3-phosphate dehydrogenase from trypanosoma cruzi. highly oxygenated flavones and isoflavone were the most actives.
Saponins from Swartzia langsdorffii: biological activities
Magalhes Aderbal Farias,Tozzi Ana Maria Goulart de Azevedo,Santos Celira Caparica,Serrano Deborah Regina
Memórias do Instituto Oswaldo Cruz , 2003,
Abstract: The presence of saponins and the molluscicidal activity of the roots, leaves, seeds and fruits of Swartzia langsdorffii Raddi (Leguminosae) against Biomphalaria glabrata adults and eggs were investigated. The roots, seeds and fruits were macerated in 95% ethanol. These extracts exerted a significant molluscicidal activity against B. glabrata, up to a dilution of 100 mg/l. Four mixtures (A2, B2, C and D) of triterpenoid oleanane type saponins were chromatographically isolated from the seed and fruit extracts. Two known saponins (1 and 2) were identified as beta-D-glucopyranosyl-[alpha-L-rhamnopyranosyl-(1->3)- beta-D-glucuronopyranosyl-(1->3)]-3beta-hydroxyolean-12-ene-28 -oate, and beta-D-glucopyranosyl-(1->3)-beta-D-glucuronopyranosyl-(1 ->3)]-3beta-hydroxyolean-12-ene-28-oate, respectively. These two saponins were present in all the mixtures, together with other triterpenoid oleane type saponins, which were shown to be less polar, by reversed-phase HPLC. The saponin identifications were based on spectral evidence, including 1H-1H two-dimensional correlation spectroscopy, nuclear Overhauser and exchange spectroscopy, heteronuclear multiple quantum coherence, and heteronuclear multiple-bond connectivity experiments. The toxicity of S. langsdorffii saponins to non-target organisms was prescreened by the brine shrimp lethality test.
Saponins from Swartzia langsdorffii: biological activities
Magalhes, Aderbal Farias;Tozzi, Ana Maria Goulart de Azevedo;Santos, Celira Caparica;Serrano, Deborah Regina;Zanotti-Magalhes, Eliana Maria;Magalhes, Eva Gon?alves;Magalhes, Luiz Augusto;
Memórias do Instituto Oswaldo Cruz , 2003, DOI: 10.1590/S0074-02762003000500022
Abstract: the presence of saponins and the molluscicidal activity of the roots, leaves, seeds and fruits of swartzia langsdorffii raddi (leguminosae) against biomphalaria glabrata adults and eggs were investigated. the roots, seeds and fruits were macerated in 95% ethanol. these extracts exerted a significant molluscicidal activity against b. glabrata, up to a dilution of 100 mg/l. four mixtures (a2, b2, c and d) of triterpenoid oleanane type saponins were chromatographically isolated from the seed and fruit extracts. two known saponins (1 and 2) were identified as b-d-glucopyranosyl-[a-l-rhamnopyranosyl-(1?3)- b-d-glucuronopyranosyl-(1?3)]-3b-hydroxyolean-12-ene-28 -oate, and b-d-glucopyranosyl-(1?3)-b-d-glucuronopyranosyl-(1 ?3)]-3b-hydroxyolean-12-ene-28-oate, respectively. these two saponins were present in all the mixtures, together with other triterpenoid oleane type saponins, which were shown to be less polar, by reversed-phase hplc. the saponin identifications were based on spectral evidence, including 1h-1h two-dimensional correlation spectroscopy, nuclear overhauser and exchange spectroscopy, heteronuclear multiple quantum coherence, and heteronuclear multiple-bond connectivity experiments. the toxicity of s. langsdorffii saponins to non-target organisms was prescreened by the brine shrimp lethality test.
Síntese de regiois?meros quirais a partir de D-manitol: obten??o de uma mistura de álcoois acetilênicos
Citó, Ant?nia Maria das Gra?as Lopes;Araújo, Bruno Quirino;Lopes, José Arimatéia Dantas;Magalhes, Aderbal Farias;Magalhes, Eva Gon?alves;
Química Nova , 2009, DOI: 10.1590/S0100-40422009000900023
Abstract: the synthesis of chiral acetylenic regioisomers was described by using an appropriate intermediate such as isopropylidene glycerol, a synthon widely used in the enantioselective syntheses. this intermediate was prepared from d-mannitol. the nine obtained compounds have been characterized by their respective spectral data. the mixture of chiral acetylenic alcohols showed activity against escherichia coli when tested through the monitoring of co2 released during microbial respiration by using a conductimetric system.
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