DEFAR - Artigos publicados em periódicos
URI permanente para esta coleçãohttp://www.hml.repositorio.ufop.br/handle/123456789/531
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Item Imines and lactones derived from friedelanes and their cytotoxic activity.(2018) Aguilar, Mariana Guerra de; Sousa, Grasiely Faria de; Evangelista, Fernanda Cristina Gontijo; Sabino, Adriano de Paula; Vieira Filho, Sidney Augusto; Duarte, Lucienir PainsFriedelan-3-one (1) and friedelane-3,16-dione (2) isolated from leaves and branches of Maytenus robusta Reissek were subjected to structural modifications via nucleophilic addition to the carbonyl group and Baeyer-Villiger oxidation in order to synthesize potential cytotoxic compounds. The oximes friedelane-3-hydroxyimino (3) and 3-hydroxyiminofriedelan-16-one (4) together with the lactones friedelane-3,4-lactone (5) and 3,4-lactonefriedelan-16-one (6) were characterized by IR and NMR spectroscopic analyses. Compounds 4 and 6 are reported for the first time. Cytotoxic screening via MTT assay in human leukemia cell lines (THP-1 and K562) demonstrated no significant improvement of compounds 3-6 when compared to the starting materials. Only compounds 3 and 5 demonstrated an improvement against K562 cells. However, the same assay on ovar- ian and breast cancer cell lines (TOV-21G and MDA-MB-231) showed a reduction in the IC50 for compounds 4-6, indicating that ring A modifications may enhance the biological potential.Item Constituintes químicos e efeito ecotoxicológico do óleo volátil de folhas de Eucalyptus urograndis (Mirtaceae).(2010) Araújo, Fabíola Oliveira Lino de; Rietzler, Arnola Cecília; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Carazza, Fernando; Vieira Filho, Sidney AugustoThe volatile oil from the leaves of E. urograndis was analyzed by GC and GC-MS. It was identified 10 compounds in which, orto-cimene (41.4%) and 1,8-cineol (25.8%) were the main constituents. The induction of deleterious effect to aquatic organisms due to the presence of volatile oil lixiviated from E. urograndis leaves was studied using Daphnia laevis and D. similis as bioindicators. Through the results of toxicological tests it was possible to show that the litterbag of E. urograndis represents a risk factor for the aquatic ecosystem of lakes and rivers that are in the surrounding area of large scale Eucalyptus plantations. The method can be used for monitor the quality of these types of aquatic environments.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 Selective oxidation of lupeol by iodosylbenzene catalyzed by manganese porphyrins.(2016) Martins, Dayse Carvalho da Silva; Silva, Fernando César; Meireles, Alexandre Moreira; Soares, Érico Augusto Rodrigues; Silva, Grácia Divina de Fátima; Vieira Filho, Sidney Augusto; Duarte, Lucienir Pains; Rebouças, Júlio Santos; Idemori, Ynara MarinaManganese porphyrin-catalyzed oxidation of lupeol by iodosylbenzenewas achieved undermild conditionswith low isolated yields but with remarkable selectivity, depending on the catalyst of choice. Mn(III) mesotetraphenylporphyrin and Mn(III) meso-tetrakis(4-carbomethoxyphenyl)porphyrin provided an entry for the preparation of 3β,30-dihydroxylup-20(29)-ene (6–14% yields), whereas Mn(III) β-octabromo-meso-tetrakis(4- carbomethoxyphenyl)porphyrin led to 20-oxo-3β-hydroxy-29-norlupeol (6% yield), as single products. Unreacted lupeol was recovered in quantitative yield. The oxidative transformations at lupeol C20 or C30 take place with no need for protection of C3 hydroxyl moiety.Item Psychotria viridis : chemical constituents from leaves and biological properties.(2017) Soares, Débora Barbosa da Silva; Duarte, Lucienir Pains; Cavalcanti, André Dias; Silva, Fernando César; Braga, Ariadne Duarte; Lopes, Miriam Teresa Paz; Takahashi, Jacqueline Aparecida; Vieira Filho, Sidney AugustoThe phytochemical study of hexane, chloroform and methanol extracts from leaves of Psychotria viridis resulted in the identification of: the pentacyclic triterpenes, ursolic and oleanolic acid; the steroids, 24-methylene-cycloartanol, stigmasterol and β-sitosterol; the glycosylated steroids 3-O-β-D-glucosyl-β- sitosterol and 3-O-β-D-glucosyl-stigmasterol; a polyunsaturated triterpene, squalene; the esters of glycerol, 1-palmitoylglycerol and triacylglycerol; a mixture of long chain hydrocarbons; the aldehyde nonacosanal; the long chain fat acids hentriacontanoic, hexadecanoic and heptadenoic acid; the ester methyl heptadecanoate; the 4-methyl-epi-quinate and two indole alkaloids, N,N-dimethyltryptamine (DMT) and N-methyltryptamine. The chemical structures were determined by means of spectroscopic (IR, 1H and 13C NMR, HSQC, HMBC and NOESY) and spectrometric (CG-MS and LCMS-ESI-ITTOF) methods. The study of biologic properties of P. viridis consisted in the evaluation of the acetylcholinesterase inhibition and cytotoxic activities. The hexane, chloroform, ethyl acetate and methanol extracts, the substances 24-methylene-cycloartanol, DMT and a mixture of 3-O-β-D-glucosyl-β-sitosterol and 3-O-β-D-glucosyl-stigmasterol showed cholinesterase inhibiting activity. This activity induced by chloroform and ethyl acetate extracts was higher than 90%. The methanol and ethyl acetate extracts inhibit the growth and/or induce the death of the tumor cells strains B16F10 and 4T1, without damaging the integrity of the normal cells BHK and CHO. DMT also demonstrated a marked activity against tumor cell strains B16F10 and 4T1.Item Anti-inflammatory, antimicrobial and acetylcholinesterase inhibitory activities of friedelanes from Maytenus robusta branches and isolation of further triterpenoids.(2017) Sousa, Grasiely Faria de; Aguilar, Mariana Guerra de; Dias, Danielle Ferreira; Takahashi, Jacqueline Aparecida; Moreira, Maria Eliza de Castro; Vieira Filho, Sidney Augusto; Silva, Grácia Divina de Fátima; Rodrigues, Salomão Bento Vasconcelos; Messias, Maria Cristina Teixeira Braga; Duarte, Lucienir PainsThe new pentacyclic triterpenoids friedel-1-en-3,16-dione (1), 1α,29-dihydroxyfriedelan-3-one (2) and 16β,28,29-trihydroxyfriedelan-3-one (3) were isolated from Maytenus robusta branches in addition to the known, but new for this species, triterpenoid 12α,29-dihydroxyfriedelan-3-one (4). The structures and stereochemistry of the novel triterpenoids were established by IR, 1D/2D NMR and HR-APCIMS spectral data. In addition, the biological activity of compound 2 and the previously isolated friedelanes 5–8 (friedelan-3,16-dione, 29-hydroxyfriedelan- 3-one, 29-hydroxyfriedelan-3,16-dione and 16β,29-dihydroxyfriedelan-3-one) was investigated. Compounds 2 and 8 were tested for their acetylcholinesterase properties and antimicrobial activity against the bacteria Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes, Citrobacter freundii, and the fungus Candida albicans. Compound 2 was the most active compound for both assays, with values of 32.3% acetylcholinesterase inhibition, 42% activity against the fungus Candida albicans and 34% against the bacterium Pseudomonas aeruginosa. Compounds 5–8 were assayed for their antiedematogenic activity using the carrageenan- induced paw edema assay. At maximum inflammation after three hours, compounds 6 and 8 showed 42% and 57% activity, respectively. After four hours, compounds 5 and 7 showed activity of 71% and 75% compared to 79% of the control indomethacin.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 Cytotoxicity, anti-poliovirus activity and in silico biological evaluation of constituents from Maytenus gonoclada (Celastraceae).(2014) Oliveira, Mauro Lúcio Gonçalves de; Assenço, Regina Aparecida Gomes; Silva, Grácia Divina de Fátima; Lopes, Júlio César Dias; Silva, Fernando César; Lanna, Maria Célia da Silva; Magalhães, José Carlos de; Duarte, Lucienir Pains; Vieira Filho, Sidney AugustoObjective: The in silico free access web tools PASS online and ChemMapper were used to predict potential biological activities of compounds 1 to 8 isolated from Maytenus gonoclada (Celastraceae). The constituents 4’-O-methylepigalocatequin (6), tingenone (7) and proanthocyanidin A (8), and ethanolic extracts were subjected to in vitro cytotoxicity using VERO cells and anti-Poliovirus assays. Methods: QSAR and molecular superposition, correlating the average number of pharmacophores were used in the prediction studies. Cellular line VERO ATCC CCL-81 was used to determine anti-Poliovirus effect, observed by colorimetric (MTT) method. The annexing V/propidium iodide assay was used to determine the occurrence of apoptosis in the cytotoxicity assays. Results: The experimental results found for constituents 6-8 were in accordance with observed data obtained through PASS online and ChemMapper simulation. Conclusion: Compound 7 showed higher cytotoxic and apoptosis induction properties, and 6 and 8 presented anti-Poliovirus activity.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 Samaras of Austroplenckia Populnea (Celastraceae) : new constituents and effect of extracts and friedelin on germination of Bidens Pilosa (Asteraceae).(2014) Caneschi, Carolina Milagres; Souza, Shiara Martins de; Certo, Thais Seixas; Souza, Gustavo Henrique Bianco de; Campos, Michele Soares Tacchi; Duarte, Lucienir Pains; Silva, Grácia Divina de Fátima; Gomes, Marcos de Souza; Vieira Filho, Sidney AugustoObjective: Evaluation of the impact of extracts and constituents from samaras of Austroplenckia populnea on percentage of seed germination (%SG), germination speed index (GSI), length of rootlets (LR), seedling length (SL), and on dry mass (DM) of Bidens pilosa L weed. Methods: The powder of samaras was extracted with organic solvents providing the hexane (SAPEH), chloroform (SAPEC), ethyl acetate (SAPEAE) and ethanol (SAPEE) extracts. The terpene 1 was isolated from SAPEH by means of column and thin layer chromatography and identified through NMR spectroscopy. Each extract and 1 were subjected to growth inhibition assays evaluating the following parameters: %SG, GSI, LR, SL and DM, with five repetitions. Results: The compounds Friedelin (1), 7-hydroxy-clerodan-3-en-16,15:18,20-diolide (2), 3,5,7,4'-tetrahydroxy-6-methoxy-8-prenylflavanone (3), tetradecanamide (4), and 4-hydroxy-1,6,15-acetyloxy-8,9-benzoyloxy-agarofurane (5) were isolated from hexane extract of samaras of A. populnea and identified by spectroscopic data. The compounds 2, 3 and 5 were not previously described as being chemical constituents from Celastraceae family. In addition, the novel compounds 3 and 5 were described here for the first time. Substantial effect on the germination of B. pilosa L. (picãopreto) was observed after treatment of seeds with nonpolar extracts from Samaras of A. populnea. Friedelin inhibited the seed germination in the tested concentrations showing toxic properties against picão-preto. Conclusion: The germination inhibition of seeds was higher using nonpolar extracts than polar extract. Friedelin inhibited the seed germination in the tested concentrations showing toxic properties against B. pilosa.