DEFAR - Artigos publicados em periódicos
URI permanente para esta coleçãohttp://www.hml.repositorio.ufop.br/handle/123456789/531
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Item Pentacyclic triterpenes from Maytenus genus as acetylcholinesterase inhibitors.(2014) Rodrigues, Vanessa Gregório; Silva, Fernando César; Duarte, Lucienir Pains; Takahashi, Jacqueline Aparecida; Matildes, Bibiane Lindsay Guimarães; Silva, Grácia Divina de Fátima; Miranda, Roqueline Rodrigues Silva de; Vieira Filho, Sidney AugustoObjective: Species of the Maytenus genus have been used in traditional medicine to treat a wide variety of human diseases. These species represent a promising source of bioactive substances of pharmacological interest. As part of a research project on phytochemical and biological activity studies of the low polarity extracts of the Maytenus genus, the extracts and eleven known pentacyclic triterpenes isolated from roots of Maytenus imbricata, and branches of Maytenus gonoclada were investigated for acetylcholinesterase inhibitory property. Methods: The acetylcholinesterase inhibition was evaluated by direct thin layer chromatography bioautography and microplate assays. Results: The crude extracts did not exhibit acetylcholinesterase inhibitory activity, but pentacyclic triterpenes, 3-oxo-11α-hydroxylup-20(29)-ene, 3-oxo-29-hydroxyfriedelane and 3,7-dioxofriedelane were active when compared to the standard compound physostigmine (eserine). Conclusion: The in vitro acetylcholinesterase inhibition property of these three pentacyclic triterpenes from Maytenus genus gives them the potential compounds to be applied in the treatment of Alzheimer’s disease.Item Triterpene esters isolated from leaves of Maytenus salicifolia Reissek.(2007) Miranda, Roqueline Rodrigues Silva de; Silva, Grácia Divina de Fátima; Duarte, Lucienir Pains; Vieira Filho, Sidney AugustoThe triterpene ester (3b)-olean-18-en-3-yl stearate (1), together with (3b)-urs-12-en-3-yl stearate (2), and (3b)-lup-20(29)-en-3-yl stearate (3) were isolated from leaves of Maytenus salicifolia Reissek (Celastraceae). The structure of 1, a new compound, including its configuration, was established by 1H, 13C, and DEPT-135 NMR data, including 2D experiments( HSQC, HMBC, COSY, and NOESY). The molecular mass (692 Da) was confirmed by gas chromatography coupled with mass spectrometry (CG/ MS).Item Structural determination of 3beta-stearyloxy-urs-12-ene from Maytenus salicifolia by 1D and 2D NMR and quantitative 13C NMR spectroscopy.(2006) Miranda, Roqueline Rodrigues Silva de; Silva, Gracia Divina de Fátima ; Duarte, Lucienir Pains; Fortes, Isabel Cristina Pereira; Vieira Filho, Sidney AugustoSix pentacyclic triterpenoids, 3b-stearyloxy-urs-12-ene (1), friedelin (2), 3b-friedelinol (3), a-amyrin (4), b-amyrin (5), and lupeol (6), have been isolated from the hexane extract of Maytenus salicifolia Reissek (Celastraceae) leaves. The molecular and structural formula as well as the stereochemistry of a new pentacyclic triterpene (1) were determined using data obtained from 1H and 13C NMR spectra, DEPT135 and by 2D HSQC, HMBC, COSY and NOESY experiments. The molecular formula C48H84O2 was established using quantitative 13C NMR, and the molecular weight (692 Da) was confirmed by elemental analysis and mass spectrometry (GC-MS).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 Antimicrobial activity of synthetic bornyl benzoates against Trypanosoma cruzi.(2012) Corrêa, Paulo Roberto Ceridóreo; Miranda, Roqueline Rodrigues Silva de; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Okuma, Adriana Akemi; Carazza, Fernando; Díaz, José Andrés Morgado; Pinge Filho, Phileno; Yamauchi, Lucy Megumi; Nakamura, Celso Vataru; Ogatta, Sueli Fumie YamadaWe report here for the first time the in vitro effects of (1S,2R,4S)-1,7,7-trimethyl-bicyclo[2.2.1]heptan-2-yl- 39,49,59-trimethoxy benzoate (1) and (1S,2R,4S)-1,7,7-trimethyl-bicyclo[2.2.1]heptan-2-yl benzoate (2) on the growth and ultrastructure of Trypanosoma cruzi. These two synthetic compounds exerted an antiproliferative effect on the epimastigote forms of the parasite. The ICs50/72h of two synthetic L-bornyl benzoates, 1 and 2, was 10.1 and 12.8 mg/ml, respectively. Both compounds were more selective against epimastigotes than HEp-2 cells. Ultrastructural analysis revealed intense cytoplasmic vacuolization and the appearance of cytoplasmic materials surrounded by membranes. The treatment of peritoneal macrophages with compounds 1 and 2 caused a significant decrease in the number of T. cruzi-infected cells. L-Bornyl benzoate derivatives may serve as a potential source for the development of more effective and safer chemotherapeutic agents against T. cruzi infections.Item Antinociceptive and edematogenic activity and chemical constituents of Talinum paniculatum Willd.(2010) Ramos, Maria Perpétua Oliveira; Silva, Grácia Divina de Fátima; Duarte, Lucienir Pains; Peres, Valdir; Miranda, Roqueline Rodrigues Silva de; Souza, Gustavo Henrique Bianco de; Belinelo, Valdenir José; Vieira Filho, Sidney AugustoTalinum paniculatum (Portulacaceae) is popularly known in the region of Patos de Minas, Minas Gerais State, Brazil, as “Maria Gorda” or “Benção-de-Deus” and in traditional medicine it is used to treat inflammatory processes in general. After dried and fragmented, the plant was sequentially submitted to exhaustive percolation with hexane, ethyl acetate and methanol. The crude extracts were investigated for their anti-edematogenic and anti-nociceptive activities through formalin-induced paw edema model. In comparison with a non-steroidal anti-inflammatory drug (NSAID) indomethacin, the hexane and ethyl acetate extracts showed higher anti-edematogenic and anti-nociceptive activity. In addition, through phytochemical studies, from these extracts were isolated and identified potassium nitrate (1), the mixture of long chain hiodrocarbons hentriacontane (2), dotriacontane (3), tritriacontane (4) and pentatriacontane (5). heneicosanoic acid (6), the ester nonacosyl nonacosanoate (7), urea (8), 3-O-b -Dglucosyl- b -sitosterol (9); the mixture of b -sitosterol (10) and stigmasterol (11), and a pentaciclyc triterpene 3-O-acethyl-aleuritolic acid (12). X-Ray difratometry was used for the characterization of inorganic constituent. TLC, HR-CG and spectrometric methods (IR. 1H and 13C NMR) were used to identify the structures of organic compounds. To the best of our knowledge, it is the first time that compound 1 to 8 and 12 are cited as constituents of T. paniculatum.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 Four Brazilian Maytenus salicifolia Reissek (Celastraceae) groups studied by TLC and UV/Vis spectrophotometry.(2009) Valladão, Frederico Nunes; Miranda, Roqueline Rodrigues Silva de; Vale, Fernando Henrique Aguiar; Valladao, Sara Araujo; Silva, Grácia Divina de Fátima; Duarte, Lucienir Pains; Okano, Rita Maria de Carvalho; Messias, Maria Cristina Teixeira Braga; Vieira Filho, Sidney AugustoA grande variedade de angiospermas apontou a necessidade do desenvolvimento de sistemas de classificação botânica apoiada pela fitoquímica, bioquímica e outras. Recentemente, técnicas de análise utilizadas para o isolamento e caracterização de metabólitos secundários vêm sendo empregadas como métodos auxiliares rápidos e eficientes para identificação e classificação de espécies vegetais. M. salicifolia é popularmente conhecida no Brasil, como “cafezinho”. O chá obtido a partir de folhas frescas é usado topicamente para aliviar pruridos e sintomas alergiformes. Este trabalho apresenta a utilização do CCD em sílica gel e espectrofotometria no UV / Vis como métodos auxiliares na identificação botânica de M. salicifolia. Os resultados demonstraram que este processo pode ser usado na diferenciação de plantas do mesmo gênero, assim como detectar variações químicas entre indivíduos de uma mesma espécie.Item New triterpenes from Maytenus robusta : structural elucidation based on NMR experimental data and theoretical calculations.(2012) Sousa, Grasiely Faria de; Duarte, Lucienir Pains; Alcântara, Antônio Flávio de Carvalho; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Miranda, Roqueline Rodrigues Silva de; Oliveira, Djalma Menezes de; Takahashi, Jacqueline AparecidaLeaves of Maytenus robusta (Celastraceae) were subjected to phytochemical investigation mainly directed at the isolation of pentacyclic triterpenes. The compounds friedelin (1), β-friedelinol (2), 3-oxo-21β-H-hop-22(29)-ene (7), 3,4-seco-friedelan-3,11β- olide (8), 3β-hydroxy-21β-H-hop-22(29)-ene (9), 3,4-seco-21β-H-hop-22(29)-en-3-oic acid (10), 3,4-seco-friedelan-3-oic acid (11), and sitosterol were identified in the hexane extract of M. robusta leaves. Compounds 8 and 9 are described herein for the first time. The structure and stereochemistry of both compounds were experimentally established by IR, HRLC-MS, and 1D (1H, 13C, and DEPT 135) and 2D (HSQC, HMBC and COSY) NMR data and supported by correlations with carbon chemical shifts calculated using the DFT method (BLYP/6-31G* level). Compounds 7 and 10 are also described for the first time, and their chemical structures were established by comparison with NMR data of similar structures described in the literature and correlations with BLYP/6-31G* calculated carbon chemical shifts. Compound 9, a mixture of 11 and sitosterol, and 3β,11β-dihydroxyfriedelane (4) were evaluated by the Ellman’s method and all these compounds showed acethylcholinesterase inhibitory properties.Item Evaluation of antibacterial activity of “Mangabarana” Austroplenckia populnea Reissek (Celastraceae).(2009) Miranda, Roqueline Rodrigues Silva de; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Carvalho, Paulo Blaya de; Messas, Ana CristinaAustroplenckia populnea (Mangabarana) é popularmente utilizada em Minas Gerais, Brasil, para o tratamento de disenterias. A ela também são atribuídas propriedades antitumoral e antiúlcera. Extratos de partes desta planta obtidos com solventes de diferentes polaridades e triterpenos pentacíclicos (TTPCs) isolados destes, por métodos fitoquímicos foram submetidos a testes de atividade antibacteriana. Os resultados mostraram a existência desta atividade e abriram perspectivas para a continuidade dos estudos com outros compostos orgânicos isolados desta planta.