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New spectral data of some flavonoids from Deguelia hatschbachii A.M.G. Azevedo
Magalh?es, Aderbal F.;Tozzi, Ana M. G. A.;Magalh?es, 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.
New spectral data of some flavonoids from Deguelia hatschbachii A.M.G. Azevedo  [cached]
Magalh?es Aderbal F.,Tozzi Ana M. G. A.,Magalh?es 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 from Lonchocarpus muehlbergianus
Magalh?es, Aderbal F.;Tozzi, Ana M.G.A.;Magalh?es, 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.
Flavonoids from Lonchocarpus muehlbergianus  [cached]
Magalh?es Aderbal F.,Tozzi Ana M.G.A.,Magalh?es 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.
Synthetic model of a new deoxybenzoin derivative from Deguelia hatschbachii A.M.G. Azevedo
Magalh?es, A. F.;Magalh?es, E. G.;Trazzi, G.;Moraes, V. R. de S.;
Eclética Química , 2005, DOI: 10.1590/S0100-46702005000100006
Abstract: in this paper we describe the synthesis of 2′,4′-dimethoxy-8-(propyl-2-one)-deoxybenzoin, a new compound employed as a model for the comparison with the respective spectral data for 6',4-dihydroxy-3'-(3,3- dimethylallyl)-2",2"-dimethylchromene(5",6":5',4')-2'-methoxy-8-(propyl-2-one) deoxybenzoin, recently isolated from deguelia hatschbachii a.m.g. azevedo. both compounds have a "propyl-2-one" group attached to c-8 of the deoxybenzoin skeleton, for which there is no precedent in the literature. the friedel-crafts reaction of 1,3-dimethoxybenzene with phenylacetyl chloride furnished 2′,4′-dimethoxydeoxybenzoin, that after reaction with allyl bromide gave 2′,4′-dimethoxy-8-(allyl)-deoxybenzoin . wacker oxidation gave the desired model compound in 15% overall yield. the corresponding spectral data reinforced the structure previously determined for the natural product.
Additional flavonoids from Lonchocarpus yucatanensis and L. xuul
Borges-Argáez, Rocío;Díaz, Maria Esther Poot;Waterman, Peter G.;Pe?a-Rodríguez, Luis M.;
Journal of the Brazilian Chemical Society , 2005, DOI: 10.1590/S0103-50532005000600028
Abstract: two new natural flavanones, 5-hydroxy-6,7-(2",2"-dimethylchromene)flavanone (1) and 5-methoxy-3-hydroxy-6,7-(2",2"-dimethylchromene)flavanone (2), were isolated from the root extracts of l. yucatanensis and l. xuul, respectively. additionally, four known metabolites, the glycosidic flavonoids quercetin-3-rhamnoglucoside and kaempferol-3-rhamnoglucoside, together with 4-hydroxy-n-methyl-proline, and p-coumaric acid methyl ester, were isolated for the first time from the leaves of l. xuul. the various metabolites were identified on the basis of their spectroscopic data and by comparison with those reported in the literature.
A identidade do Timbó-verdadeiro: Deguelia utilis (A.C.Sm.) A.M.G.Azevedo (Leguminosae -- Papilionoideae)
TOZZI, ANA M. G. DE AZEVEDO;
Revista Brasileira de Biologia , 1998, DOI: 10.1590/S0034-71081998000300016
Abstract: the original description of lonchocarpus utilis a.c.sm. is augmented by the inflorescence and flower data, since the species was established under a sterile material. considering the reproductive aspects are now described, the species is transferred to the genus deguelia and a epitype is designated. it is also proposed the synonymization of lonchocarpus nicou var. ianguidus f.j.herm.
A identidade do Timbó-verdadeiro: Deguelia utilis (A.C.Sm.) A.M.G.Azevedo (Leguminosae Papilionoideae)
TOZZI ANA M. G. DE AZEVEDO
Revista Brasileira de Biologia , 1998,
Abstract: A descri o original de Lonchocarpus utilis A.C.Sm. é ampliada pela inclus o de informa es sobre a inflorescência e flor, uma vez que a espécie foi estabelecida com base em material estéril. Considerando que aspectos reprodutivos s o descritos aqui, a espécie é transferida para o gênero Deguelia e é designado um epitipo. Também é proposta a sinonimiza o de Lonchocarpus nicou var. languidus F.J.Herm.
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;Magalh?es, Eva G.;Magalh?es, 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.
Enzymatic inhibition studies of selected flavonoids and chemosystematic significance of polymethoxylated flavonoids and quinoline alkaloids in Neoraputia (Rutaceae)  [cached]
Moraes Valéria R. de S.,Tomazela Daniela M.,Ferracin Ricardo J.,Garcia Cleverson F.
Journal of the Brazilian Chemical Society , 2003,
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.
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