22 research outputs found

    New spectral data of some flavonoids from Deguelia hatschbachii A.M.G. Azevedo

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    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.Entre os flavonóides isolados de Deguelia hatschbachii¹ encontram-se escandenina (1), robustato de metila (2) e 4',5-diidroxi-6-(3,3-dimetilalila)-7-metoxiflavanona (3) que foram identificados pela comparação dos dados espectroscópicos previamente publicados. A obtenção de novos dados espectroscópicos (RMN, RMN-2D e EM/EM) permitiu a atribuição dos deslocamentos químicos de todos os hidrogênios e carbonos nos espectros de RMN ¹H e 13C destas substâncias, assim como a elucidação dos caminhos de fragmentação de 1-3 no espectrômetro de massas.133137Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Flavonoids Of Lonchocarpus Montanus A.m.g. Azevedo And Biological Activity.

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    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-(alpha,alpha-dimethylallyl)-2, 2-dimethylpyrano-(5,6:3',4')-dibenzoylmethane (1), 2'-methoxy-8-(alpha,alpha-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 Staphylococcus 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.79351-6

    New hopane triterpene from Eleocharis sellowiana (Cyperaceae)

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    A new triterpene named 3alpha-hydroxy-13alpha,17alpha,21beta-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.Do extrato hexânico de Eleocharis sellowiana foram isolados o novo triterpeno 3alfa-hidroxi-13alfa,17alfa,21beta-hopano-15,19-diona e hexadecanoato de E-fitila, caracterizados por dados de RMN e EM.803806Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    The chemistry of Brazilian Lauraceae XLVI. Notes on Aniba species

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    Aniba affinis, A. cylindriflora and A. mas (Lauraceae) were found to contain respectively benzofuranoid (and a previously unknown bicyclo [3, 2, 1] octanoid) neolignans, 6-styryl-2-pyrones and 6-styryl-4-methoxy-2-pyrones.A madeira do tronco das espécies amazônicas Aniba affinis, A. cylindriflora e A. mas contém respectivamente neolignanas benzofuranoídicas (e uma biciclo [3, 2, 1] octanoídica previamente desconhecida), 6-estiril-2-pironas e 6-estiril-4-metoxi-2-pironas

    Enzymatic inhibition studies of selected flavonoids and chemosystematic significance of polymethoxylated flavonoids and quinoline alkaloids in Neoraputia (Rutaceae)

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    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.Nosso interesse quimiotaxonômico sobre Neoraputia nos estimulou a examinar N. paraensis, visando a busca de alcalóides. As frações foram monitoradas via RMN ¹H e ESI-EM/EM e foram analisadas somente aquelas cujos espectros apresentavam características de alcalóides do ácido antranílico e flavonóides não isolados anteriormente. Foram isolados do caule os alcalóides flindersina, skimmianina, 8-metoxiflindersina e dictamnina; das folhas os flavonóides 3',4',7,8-tetrametoxi-5,6-(2,2-dimetilpirano)-flavona, 3',4',5,7,8-pentametoxiflavona, 5-hidroxi-3',4',6,7-tetrametoxiflavona, 3',4'-metilenodioxi-5,6,7-trimetoxiflavona e 5-hidroxi-3',4'-metilenodioxi-6,7-dimetoxiflavona,. Os alcalóides do ácido antranílico não foram encontrados em dez anos. Vários flavonóides isolados de N. paraensis, N. magnifica, Murraya paniculata, enxerto de Citrus sinensis (Rutaceae) e Lonchocarpus montanus (Leguminosae) foram testados frente a gliceraldeído-3-fosfato desidrogenase de Trypanosoma cruzi, visando verificar seus potenciais em inibir a atividade da enzima. Os flavonóides polimetoxilados e um isoflavonóide foram os mais ativos.380387Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Swartziarboreol Diterpenes From Swartzia Langsdorffii Raddi.

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    Two new swartziarboreol diterpenes (1 and 2) and swartziarboreol C were isolated from the petroleum ether extract of the roots of Swartzia langsdorffii. Their structures were elucidated by spectroscopic evidence. The biological activity of the root extracts and 2 was evaluated through bioautography and brine shrimp lethality assays.681290-

    New Prenylated Metabolites Of Deguelia Longeracemosa And Evaluation Of Their Antimicrobial Potential.

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    The analysis of root extracts from Deguelia longeracemosa (Benth.) A.M.G. Azevedo yielded fifteen prenylated metabolites. Nine of them are novel, and their molecular structures were determined through spectral analyses (UV, IR, MS and NMR) as being five derivatives of 4-hydroxy-3-phenylcoumarin: 4-hydroxy-3-(4'-hydroxyphenyl)-5-methoxy-6-(8',9'-epoxy-9'-methylbutyl)-2'',2''-dimethylpyrano-(5'',6'':8,7)-coumarin; 4-hydroxy-3-(3',4'-methylenedioxyphenyl)-5-methoxy-6-(3,3-dimethylallyl)-2'',2''-dimethypyrano-(5'',6'':8,7)-coumarin; 4-hydroxy-3-(3'-hydroxy-4'-methoxyphenyl)-5-methoxy-6-(3,3-dimethylallyl)-2'',2''-dimethylpyrano-(5'',6'':8,7)-coumarin; 4-hydroxy-3-(3'-hydroxy-4'-methoxyphenyl)-5-methoxy-2'',2''-dimethylpyrano-(5'',6'':6,7)-coumarin and 4-hydroxy-3-[4'-O-(3,3-dimethylallyl)phenyl]-5-methoxy-2'',2''-dimethylpyrano-(5'',6'':6,7)-coumarin, three derivatives of 1,2-diphenyl-1,2-ethanodione (alpha-oxodeoxybenzoin derivatives): 1-[6-hydroxy-2-methoxy-3-(3,3-dimethylallyl)-2'',2''-dimethylpyrano-(5'',6'':5,4)- ]-2-(4'-hydroxyphenyl)-1,2-ethanedione; 1-[6-hydroxy-2-methoxy-2'',2''-dimethylpyrano-(5'',6'':3,4)]-2-(4'-methoxyphenyl)-1,2-ethanedione; 1-[6-hydroxy-2-methoxy-2'',2''-dimethylpyrano-(5'',6'':3,4)]-2-(3',4'-methylenedioxyphenyl)-1,2-ethanedione and one derivative of deoxybenzoin: 2,4'-dimethoxy-6-hydroxy-2'',2''-dimethylpyrano-(5'',6'':3,4)-deoxybenzoin. The antimicrobial activity of roots extracts and some isolated compounds was screened through bioautography against bacteria and fungi.72358-6

    New spectral data of some flavonoids from Deguelia hatschbachii A.M.G. Azevedo

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    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

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    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
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