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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.
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.
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.
El género Deguelia (Leguminosae, Papilionoideae, Millettieae) en Mesoamérica, una especie nueva y una combinación nueva The genus Deguelia (Leguminosae, Papilionoideae, Millettieae) in Mesoamerica, a new species and a new combination  [cached]
Mario Sousa S.
Revista mexicana de biodiversidad , 2009,
Abstract: Se presenta una revisión taxonómica del género Deguelia Aubl. (Millettieae: Leguminosae) para Mesoamérica; para ello fue necesario describir e ilustrar a una nueva especie, Deguelia alata M. Sousa y proponer una nueva combinación, D. densiflora (Benth.). A. M. G. Azevedo ex M. Sousa, para una especie previamente incluida en el género Lonchocarpus. A revision of the genus Deguelia Aubl. (Millettieae: Leguminosae) in Mesoamerica is presented. A new species, Deguelia alata is described and illustrated, and a new combination, D. densiflora is proposed for a species formerly included in Lonchocarpus.
Dihydroflavonols from the leaves of Derris urucu (Leguminosae): structural elucidation and DPPH radical-scavenging activity
L?bo, Lívia T.;Silva, Geilson A. da;Ferreira, Malisson;Silva, Milton N. da;Santos, Alberdan S.;Arruda, Alberto C.;Guilhon, Giselle M. S. P.;Santos, Lourivaldo S.;Borges, Rosivaldo dos Santos;Arruda, Mara Silvia P.;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009000600013
Abstract: derris urucu is an amazonian plant with insecticide and ichthyotoxic properties. studies with this species show the presence of flavonoids, mainly rotenoids, as well as stilbenes. the ethanol extract of the leaves of derris urucu (leguminosae) afforded three new dihydroflavonols named urucuol a (1), b (2) and c (3), and the dihydroflavonol isotirumalin (4). their structures were elucidated by extensive analysis of 1d and 2d nmr, uv and ir spectra and ms data and comparison with literature data. the isolated compounds (1-4) were evaluated for dpph? radical scavenging activity and showed a relatively lower antioxidant ability compared to the commercial antioxidant trans-resveratrol.
Flavonoids from the leaves of Deguelia utilis (Leguminosae): structural elucidation and neuroprotective properties
Oliveira, Dalglish G. de;Almeida, Cecília M. C. de;Silva, Consuelo Y. Y. e;Arruda, Mara S. P.;Arruda, Alberto C.;Lopes, Dielly C. F.;Yamada, Elizabeth S.;Costa, Edmar T. da;M. Filho, Arnaldo Jorge;Silva, Milton N. da;
Journal of the Brazilian Chemical Society , 2012, DOI: 10.1590/S0103-50532012005000065
Abstract: five new flavonoids, 5,3'-dihydroxy-4'-methoxy-2'',2''-dimethylchromene-(5'',6'':6,7)dihydroflavonol (1), 5,3'-dihydroxy-7,4'-dimethoxy-6,8-dimethylallyl-dihydroflavonol (2), 5,3'-dihydroxy-4'-methoxy-8-allyl-2'',2''-dimethylchromene-(5'',6'':6,7) flavanone (3), 5,3'-dihydroxy-7,4'-dimethoxy-6,8-dimethylallyl-flavanone (4), 3,5,3'-trihydroxy-7,4'-dimethoxy6,8-dimethylallyl-flavanol (5), together with the stilbenes 4-methoxylonchocarpene (6) and lonchocarpene (7) were isolated from the leaves of deguelia utilis. their chemical structures were established on the basis of nmr (nuclear magnetic resonance) spectral data and hresitof-ms (electrospray ionization-high resolution time-of-flight mass spectrometry). also, in order to investigate potential cytoprotective effects of these flavonoids, we used a fraction eluted with hexane:etoac containing all seven flavonoids, in an in vitro model of neurodegeneration, using hippocampal primary cultures from neonatal (pnd2-p3) rats exposed to rotenone, a mitochondrial complex i inhibitor. there was a significant reduction in cell viability (19.4 ± 1.6%) when the cultures were exposed to 30 nmol l-1 rotenone for 72 h. concomitant exposure of the cultures to the fr3 (5 μg ml-1) and 30 nmol l-1 rotenone resulted in values of cell viability similar to control groups (99.6 ± 4.8%), strongly suggesting a cytoprotective effect for this flavonoid-rich fraction.
El género Deguelia (Leguminosae, Papilionoideae, Millettieae) en Mesoamérica, una especie nueva y una combinación nueva
Sousa S., Mario;
Revista mexicana de biodiversidad , 2009,
Abstract: a revision of the genus deguelia aubl. (millettieae: leguminosae) in mesoamerica is presented. a new species, deguelia alata is described and illustrated, and a new combination, d. densiflora is proposed for a species formerly included in lonchocarpus.
Cyclodimerization of Stilbenes and Styrenes Catalyzed by Heteropolyacid Supported on Silica  [PDF]
E. N. Alesso,J. Aguirre,B. Lanta?o,L. Finkielsztein,G. Y. Moltrasio,P. G. Vázquez,L. R. Pizzio,C. Caceres,M. White,H. J. Thomas
Molecules , 2000, DOI: 10.3390/50300414
Abstract: Several stilbenes and styrenes have been treated with heteropolyacid] (HPA) supported over silice. The compounds obtained were characterized by 1H and 13C- NMR and the yields were compared with those obtained using H2SO4 (c) and ethyl poliphosphate] (PPE).
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