Overhauser
Mostrando 1-12 de 172 artigos, teses e dissertações.
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1. Antiproliferative Activity of Dibenzoylmethanes from Root Bark of Muellera filipes (Benth) M.J. Silva & A.M.G. Azevedo
Three new dibenzoylmethane derivatives, (E)-3,4-methylenedioxy-2'-methoxy-2'',2''-dimethylpyrano-(5'',6'':3',4')-7-methoxychalcone, 2'-hydroxy-5'(3'''',3''''-dimethylallyl)-8-(α,α-dimethylallyl)-furano-(4'',5'':3'4')-dibenzoylmethane and 2'-O-(3'',3''-dimethylallyl)-8-(α,α-dimethylallyl)-furano-(4'',5'':3'4')-dibenzoylmethane, were isolated from a dichlo
J. Braz. Chem. Soc.. Publicado em: 2017-08
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2. A C1 Beam Element Based on Overhauser Interpolation
Abstract A new C1 element is proposed to model Euler-Bernoulli beams in one and two-dimensional problems. The proposed formulation assures C1 continuity requirement without the use of rotational degrees of freedom, used in traditional elements, through the use of an Overhauser interpolation scheme for bending displacements. The principle of virtual displacem
Lat. Am. j. solids struct.. Publicado em: 2017-01
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3. Sesquiterpenoids from Nectandra megapotamica (Lauraceae)
Five sesquiterpenoid oxides, named nectandrene A, B, C, D, and E, were isolated from the essential oil of the leaves of Nectandra megapotamica. Their structures were elucidated by spectroscopic analysis, and the relative configurations were proposed by their nuclear Overhauser effect (NOESY) spectrum. Three of these isolated compounds displayed significant a
J. Braz. Chem. Soc.. Publicado em: 2017-01
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4. Angelocunhol: New Erythroxylane Diterpene and Other Compounds from Simira sampaioana (Rubiaceae)
The first Simira sampaioana (Rubiaceae) phytochemical study allowed the isolation and structural determination of a new erythroxylane diterpene named Angelocunhol, 11β,12α-dihydroxy-2,4(18),15-eritroxilatrien-1-one, together with 14 known compounds: simirane B, harman, maxonine, isomalindine, malindine, sitost-4-en-6-ol-3-one, estigmast-4,22-dien-6-ol-3-on
J. Braz. Chem. Soc.. Publicado em: 2017-01
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5. SÍNTESE E CARACTERIZAÇÃO DE SURFACTANTES ALQUILFENIL POLIGLICOSÍDICOS A PARTIR DA AMILOSE E ALQUIL FENÓIS EXTRAÍDOS DO LCC NATURAL
The surfactants were synthesized by condensing the obtained oligosaccharides of amylose and alkyl phenols extracted from the natural cashew nut shell liquid (nCNSL). The Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared Spectroscopy (FTIR) data showed aromatic ring bands, glycosidic rings, olefins and paraffins. The Nuclear Overhauser Effect Sp
Quím. Nova. Publicado em: 2016-08
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6. A New Steroidal Saponin from the Tubers of Ophiopogon japonicus and Its Protective Effect Against Cisplatin-Induced Renal Cell Toxicity
A new furostanol saponin, ophiopogonin T, was isolated from the tubers of Ophiopogon japonicus. Its structure was established by extensive spectroscopic techniques including 1D (1H and 13C) and 2D nuclear magnetic resonance (NMR) experiments (correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond correlati
J. Braz. Chem. Soc.. Publicado em: 2016-04
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7. Detailed 1H and 13C NMR Spectral Data Assignment for Two Dihydrobenzofuran Neolignans
In this work we present a complete proton (1H) and carbon 13 (13C) nuclear magnetic resonance (NMR) spectral analysis of two synthetic dihydrofuran neolignans (±)-trans-dehydrodicoumarate dimethyl ester and (±)-trans-dehydrodiferulate dimethyl ester. Unequivocal assignments were achieved by 1H NMR, proton decoupled 13C (13C{1H}) NMR spectra, gradient-selec
J. Braz. Chem. Soc.. Publicado em: 2016-01
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8. SÍNTESE E DETERMINAÇÃO DA ESTEREOQUÍMICA RELATIVA DE UM NOVO EPÓXIDO ALDEÍDO CICLOPENTANO MONOTERPENÓIDE
In this study, we report the preparation of a new tetra-substituted epoxide aldehyde cyclopentane, which acts as a starting material for the synthesis of plinol, from (R)-(+)-epoxy-limonene. The synthesis was performed in three steps and resulted in a good yield. The structural determination was performed by 1H and 13C NMR, and the relative stereochemistry w
Quím. Nova. Publicado em: 2015-12
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9. Cytotoxic Alkaloids from Hippeastrum solandriflorum Lindl.
One new alkaloid, 2α-10bα-dihydroxy-9-O-demethylhomolycorine, in addition to seven others known alkaloids, and 5-(hydroxymethyl)furfural, piscidic acid and eucomic acid, were isolated from the bulbs of Hippeastrum solandriflorum. The structures of all compounds were determined using nuclear magnetic resonance (NMR) spectroscopic techniques: 1H NMR and 13C
J. Braz. Chem. Soc.. Publicado em: 2015-10
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10. Variable-temperature NMR and conformational analysis of oenothein B
Oenoteína B é um tanino hidrolisável dimérico com um amplo espectro de atividades biológicas, tais como antitumoral, anti-inflamatória e anti-viral. Seus espectros de ressonância magnética nuclear (RMN) à temperatura ambiente apresentam duplicações e alargamento de sinais. Experimentos de RMN uni e bidimensionais a baixas temperaturas foram úteis
J. Braz. Chem. Soc.. Publicado em: 2014-02
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11. Phenylpropanoid substituted flavan-3-ols from Trichilia catigua and their in vitro antioxidative activity
O novo flavan-3-ol contendo um substituinte fenilpropanoide apocinina E, juntamente com oito substâncias conhecidas, epicatequina, procianidina B2, procianidina B4, procianidina C1, cinchonaína Ia, cinchonaína Ib, cinchonaína IIb e cinchonaína IIa foram isoladas a partir do extrato acetona-H2O das cascas secas de Trichilia catigua. As substâncias cinch
Journal of the Brazilian Chemical Society. Publicado em: 2011-11
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12. Aspectos não perturbativos das teorias de Yang-Mills. / Non-perturbative aspects of Yang-Mills theory
Alguns aspectos não perturbativos das teorias de Yang-Mills puras em quatro dimensões Euclideanas, quantizadas no calibre de Landau, são estudados analiticamente. Por pura entendemos a teoria na ausência de matéria (férmions). Em particular, ivestigamos a geração dinâmica de massa para os gluons devido a presença de condensados de dimensão dois. E
Publicado em: 2007