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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.
Flavonoids of Lonchocarpus montanus A.M.G. Azevedo and biological activity
Magalh?es, Aderbal F.;Tozzi, Ana Maria G.A.;Magalh?es, 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.
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.
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.
Stilbenes from Deguelia rufescens var. urucu (Ducke) A. M. G. Azevedo leaves: effects on seed germination and plant growth
Lobo, Lívia T.;Silva, Geilson A. da;Freitas, Manolo C. C. de;Souza Filho, Antonio Pedro S.;Silva, Milton N. da;Arruda, Alberto C.;Guilhon, Giselle M. S. P.;Santos, Lourivaldo S.;Santos, Alberdan S.;Arruda, Mara S. P.;
Journal of the Brazilian Chemical Society , 2010, DOI: 10.1590/S0103-50532010001000007
Abstract: the amazon biodiversity may provide plants whose chemical substances are capable of controlling weeds. in this study we report the isolation and identification of five stilbenes from the leaves of "timbó vermelho" (deguelia rufescens var. urucu): 4-methoxylonchocarpene (1); 3,5-dimethoxy-4′-hydroxy-3′-prenyl-trans-stilbene (2), lonchocarpene (3), 3,5-dimethoxy-4′-o-prenyl-trans-stilbene (4) and pterostilbene (5). compounds 2 and 4 are new natural products although 2 has been previously cited as synthesis product. potential allelopathic activity for 1, 2 and 4 was evaluated over seed germination and plant growth of mimosa pudica weed. the observed effects on seed germination did not vary significantly (p > 0.05) when the analysis of phytotoxicity was performed with the substances alone, the maximum inhibition did not exceed 20%. the most intense inhibitions on radicle and hypocotyl development were found for compound 4 (p < 0.05). when tested in pairs, showed antagonism for seed germination and synergism for radicle and hypocotyl development.
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.
SCHIZACHYRIUM HATSCHBACHII (POACEAE), NUEVO REGISTRO PARA LAFLORA ARGENTINA Schizachyrium hatschbachii (Poaceae), new record for Argentinian flora
Myriam C. Peichoto,Héctor A. Keller
Bonplandia , 2010,
Abstract: Se cita a Schizachyrium hatschbachii Peichoto por primera vez para la flora argentina. Seincluyen algunas observaciones ecológicas y una clave para diferenciarla de las entidadesafines Schizachyrium hatschbachii Peichoto is cited for the first time for the Argentinian flora. Some ecological observations and the key to differentiate it from related species are included
Schizachyrium hatschbachii (Poaceae), nuevoregistro para la flora argentina
Myriam C. Peichoto,Héctor A. Keller
Bonplandia , 2008,
Abstract: Se cita a Schizachyrium hatschbachii Peichoto por primera vez para la flora argentina. Seincluyen algunas observaciones ecológicas y una clave para diferenciarla de las entidadesafines
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.
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