EFAR - Escola de Farmácia
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/451
Notícias
O curso de Farmácia em Ouro Preto foi criado em 1839, sendo a mais antiga Escola de Farmácia da América Latina.
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17 resultados
Resultados da Pesquisa
Item Complete assignment of the 1H and 13C NMR spectra of a new polyester sesquiterpene from Austroplenckia populnea.(2000) Vieira Filho, Sidney Augusto; Duarte, Lucienir Pains; Santos, Marcelo Henrique dos; Silva, Grácia Divina de Fátima; Lula, Ivana Silva; Afonso, Robson José de Cássia Franconew polyester sesquiterpene (4-hydroxy-1,2,6,15-tetraacetyl-9-benzoylagarofuran), together with known friedelane triterpenes (friedelin, -friedelinol and 28-hydroxyfriedelin), was isolated from the leaves of Austroplenckia populnea. The structure and relative stereochemistry of the new ester were based on 2D NMR spectroscopic techniques including HMBC, HMQC and NOESY.Item Flavonol triglycosides of leaves from Maytenus robusta with acetylcholinesterase inhibition.(2017) Sousa, Grasiely Faria de; Aguiar, Mariana Guerra de; Takahashi, Jacqueline Aparecida; Alves, Tânia Maria de Almeida; Kohlhoff, Markus; Vieira Filho, Sidney Augusto; Silva, Grácia Divina de Fátima; Duarte, Lucienir PainsAlthough Maytenus robusta aqueous infusions of leaves are used in Brazilian traditional medicine for stomach disease treatment, only a few chemical studies of this species are found in literature. The phytochemical investigation of methanol extract from M. robusta leaves yielded the known compound kaempferol (3) and two new flavonol glycosides: kaempferol-3-O-b-D-glucopyranosyl-(1 !3)-a-Lrhamnopyranosyl-( 1 ! 2)-b-D-glucopyranoside (1) and quercetin-3-O-b-D-glucopyranosyl-(1 !3)-a-Lrhamnopyranosyl-( 1 ! 2)-b-D-glucopyranoside (2). The chemical structures of 1 and 2 were elucidated by 1D/2D NMR, ESI–MS and ESI–MS2 spectral data. It is the first time flavonoids have been reported from M. robusta. Flavonols 1 and 2 showed 66% and 80% acetylcholinesterase (AChE) inhibition, compared to 93% of the standard eserine, by the Ellman’s method. These substances are one of the few active flavonols linked to a trisaccharide chain in the literature presenting this activity, and contribute to the screening for new types of natural AChE inhibitors.Item Two epimeric friedelane triterpenes isolated from Maytenus truncata Reiss : 1H and 13C chemical shift assignments.(2000) Meléndez Salazar, Gloria Del Carmen; Silva, Grácia Divina de Fátima; Duarte, Lucienir Pains; Lula, Ivana SilvaAn NMR study of 3˛- and 3ˇ-friedelinol is described. In addition to conventional 1D NMR methods, 2D shift-correlated NMR experiments HMQC [(1J(C,H)], HMBC [nJ(C,H); n D 2 and 3] and 2D 1H,1H-NOESY were used for 1H and 13C chemical shift assignments of these triterpenes.Item Total assignment of 1H and 13C NMR spectra of two 3,4-secofriedelanes from Austroplenckia populnea.(2001) Vieira Filho, Sidney Augusto; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Lula, Ivana Silva; Santos, Marcelo Henrique dosTwo new 3,4-secofriedelanes, 3,4-seco-28-hydroxyfriedelan-3-oic acid (1) and 3,4-secofriedelan-3-oic acid (2),were isolated from the leaves of Austroplenckia populnea (Celastraceae).The structureswere established by 2D NMR spectroscopic techniques (COSY, HMQC, HMBC and NOESY).Item Epikatonic acid from Austroplenckia populnea : structure elucidation by nmr spectroscopy and x-ray crystallography.(2002) Silva, Grácia Divina de Fátima; Duarte, Lucienir Pains; Viera Filho, Sidney Augusto; Doriguetto, Antônio Carlos; Mascarenhas, Yvone PrimeranoFrom the chloroform extract of Austroplenckia populnea, epikatonic acid, friedelin, populnonic acid, abruslactone A, salaspermic acid and 22b-epi-maytenfolic acid were isolated. The structure and stereochemistry of epikatonic acid were established by two-dimensional NMR spectroscopic techniques (HMQC, HMBC and NOESY) and later confirmed by single crystal X-ray diffraction as 3b-hydroxyolean- 12-en-29-oic acid, which unambiguously established the configuration of the hydroxyl group at C-3 as 3b-OH and the carboxyl group at C-20 as 20a-COOH. The crystal structure shows two independent molecules in the asymmetric unit. The crystal packing is stabilized by four O–H· · ·O intermolecular hydrogen bonds, which give rise to infinite double chains along the c axis.Item Constituents of fruit pulp of Maytenus salicifolia and complete 1D/2D NMR data of 3beta-hydroxy-D-B-friedo-olean-5-ene.(2010) Valladão, Frederico Nunes; Miranda, Roqueline Rodrigues Silva de; Oliveira, Gabriela Soares de; Silva, Grácia Divina de Fátima; Duarte, Lucienir Pains; Vieira Filho, Sidney AugustoA mixture of long-chain hydrocarbons constituted by nonacosane (29C, 7.5%), hentriacontane (31C, 48.3%), and tritriacontane (33C, 30.1%), the ester 1 -acetyloxymethylpentacosa-20 -enyl 10-hydroxydecanoate (2), -amyrin (3), friedelin (4), and lupeol (5), and 3 -hydroxy-D:B-friedo-olean-5-ene (6) were identified as constituents of fruits of Maytenus salicifolia Reissek (Celastraceae). The structural formula and the stereochemistry of compound 6 were established by the data obtained through 1H and 13C NMR spectroscopy, including DEPT-135 and 2D (HMQC, HMBC, and NOESY) experiments. By analysis of the spectral data, it was possible to correct seven chemical shift assignments of compound 6, which were erroneous attributed and published in the scientific literature.Item Antigiardial activity of the hexane extract of Maytenus gonoclada mart.(2012) Silva, Fernando César; Busatti, Haendel Gonçalves Nogueira Oliveira; Gomes, Maria Aparecida; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney AugustoPlants of the Maytenus genus have been used in folk medicine in Brazil for treatment of gastrointestinal motility disturbances such as diarrhea. The present study was performed to evaluate antigiardial activity of the hexane extract and triterpenes isolated from the branches of Maytenus gonoclada Mart. (Celastraceae). The hexane extract and triterpenes were examined for antigiardial activity using the colorimetric method against Giardia lamblia (ATCC 30888). The hexane extract exhibited antigiardial activity. This result may partly explain and support the use of plants of the Maytenus genus for the treatment of diarrhea in folk medicine in Brazil.Item Pentacyclic triterpenes from branches of Maytenus robusta and in vitro cytotoxic property against 4T1 cancer cells.(2014) Sousa, Grasiely Faria de; Soares, Daniel Crístian Ferreira; Mussel, Wagner da Nova; Pompeu, Nana Flora Elias; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Duarte, Lucienir PainsDois novos friedelanos, 1 e 2, e cinco triterpenos pentacíclicos conhecidos foram isolados dos galhos de Maytenus robusta. Suas estruturas químicas foram identificadas como 3,16-dioxo-29- hidroxifriedelano (1), 3-oxo-16b,29-di-hidroxifriedelano (2), 3-oxofriedelano (3), 3b-friedelinol (4), 3,16-dioxofriedelano (5), 3-oxo-29-hidroxifriedelano (6) e 3,16-dioxo-12a-hidroxifriedelano (7). A estrutura e estereoquímica dos triterpenos 1 e 2 foram estabelecidas por infravermelho (IR), ressonância magnética nuclear (NMR) 1D/2D, espectrometria de massas de alta resolução com ionização química à pressão atmosférica (HR-APCIMS) e difração de raios X de pó. A atividade citotóxica in vitro dos triterpenos 1 a 6 foi avaliada frente a células de câncer de mama murino. Os triterpenos 1 e 2 apresentaram atividade citotóxica contra células 4T1 em baixa concentração.Item Stereochemistry of 16α-hydroxyfriedelin and 3-oxo-16-methylfriedel-16-ene established by 2D NMR spectroscopy.(2009) Duarte, Lucienir Pains; Miranda, Roqueline Rodrigues Silva de; Rodrigues, Salomão Bento Vasconcelos; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Knupp, Vagner FernandesFriedelin (1), 3β-friedelinol (2), 28-hydroxyfriedelin (3), 16α-hydroxyfriedelin (4), 30-hydroxyfriedelin (5) and 16α,28-dihydroxyfriedelin (6) were isolated through fractionation of the hexane extract obtained from branches of Salacia elliptica. After a week in CDCl3 solution, 16α-hydroxyfriedelin (4) reacted turning into 3-oxo-16- methylfriedel-16-ene (7). This is the first report of a dehydration followed by a Nametkin rearrangement of a pentacyclic triterpene in CDCl3 solution occurring in the NMR tube. These seven pentacyclic triterpenes was identified through NMR spectroscopy and the stereochemistry of compound 4 and 7 was established by 2D NMR (NOESY) spectroscopy and mass spectrometry (GC-MS). It is also the first time that all the 13C-NMR and 2D NMR spectral data are reported for compounds 4 and 7.Item Antioxidant activity of Maytenus imbricata Mart., Celastraceae.(2009) Silva, Grácia Divina de Fátima; Souza, Silvia Ribeiro de; Barbosa, Luiz Cláudio de Almeida; Duarte, Lucienir Pains; Ribeiro, Sônia Machado Rocha; Queiroz, José Humberto de; Vieira Filho, Sidney Augusto; Oliveira, Márcio L. R.A atividade antioxidante, poder redutor (RP) e a atividade coletora de radicais livres (FRS) usando 2,2-difenil- 1-picrilhidrazil (DPPH), e a concentração de substâncias fenólicas totais dos extratos e substâncias isoladas das folhas, caules e raízes de Maytenus imbricata Mart. (Celastraceae) foram avaliados. Alguns extratos, a mistura de compostos fenólicos e epicatequina mostraram alto poder redutor e atividade antioxidante (DPPH) em comparação com o padrão butilhidroxianisol (BHA) e ácido gálhico (GA) utilizados no ensaio. O extrato acetato de etila das folhas mosraram alto teor de substâncias fenólicas e alto poder redutor e atividade antioxidante em relação aos outros extratos. Este fato indica haver alguma relação entre a concentração de substâncias fenólicas e o poder redutor. O solvente usado no processo de extração influencia a composição química dos extratos e, consequentemente, as atividades redutoras e antioxidantes.