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Infrared spectrum and UV-induced photochemistry of matrix-isolated 5-methoxy-1-phenyl-1H-tetrazole

Gómez-Zavaglia, Andrea; Reva, I. D.; Frija, L.; Cristiano, M. L. S.; Fausto, R.
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
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The molecular structure, vibrational spectra and photochemistry of 5-methoxy-1-phenyl-1H-tetrazole (5MPT) were studied by matrix isolation infrared spectroscopy and DFT(B3LYP)/6-311++G(d,p) calculations. According to the calculations, only one double degenerated-by-symmetry minimum exists in the ground state PES of the compound. In this structure, the dihedral angle between the two rings (phenyl and tetrazole) is ca. 30°, whereas the methoxyl group stays nearly in the plane of the tetrazole ring. In consonance with the theoretical predictions, only one molecular species was experimentally observed in the as-deposited argon matrices. Theoretical calculations were also used to help in assignment of the experimental spectrum of the compound, the calculated spectrum showing a very good agreement with the experimental data. In situ UV-irradiation ([lambda] > 235 nm) of the matrix-isolated 5MPT induced unimolecular decomposition of the compound, which led mainly to production of methylcyanate and phenylazide, this latter further reacting to yield, as final product, 1-aza-1,2,4,6-cycloheptatetraene. 3-Methoxy-1-phenyl-1H-diazirene was also observed experimentally as minor product, resulting from direct elimination of molecular nitrogen from 5MPT.; http://www.sciencedirect.com/science/article/B6TGY-4HR72GH-1/1/90b3c1e44ce4d246bfcebbe8a3a7a52a

Triazole-linked phenyl derivatives: redox mechanisms and in situ electrochemical evaluation of interaction with dsDNA

Pontinha, A. Dora R.; Lombardo, Caterina M.; Neidle, Stephen; Oliveira-Brett, Ana Maria
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
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The redox mechanism of two trisubstituted triazole-linked phenyl derivatives (CL41 and CL42) and a disubstituted triazole-linked phenyl derivative (CL2r50) were studied using cyclic, differential pulse and square wave voltammetry at a glassy carbon electrode. The CL41, CL42 and CL2r50 oxidation is a complex, pH-dependent irreversible process involving the formation of electroactive products that undergo two consecutive reversible oxidation reactions. The DNA interaction with CL41, CL42 and CL2r50 was investigated by differential pulse voltammetry using the dsDNA-electrochemical biosensor and in DNA/trisubstituted triazole incubated solutions. All three trisubstituted triazole-linked phenyl derivatives interacted with dsDNA causing morphological and oxidative damage to the dsDNA structure in a time-dependent manner. The DNA-electrochemical biosensor enabled the detection of oxidative damage to DNA following the occurrence of the 8-oxoGua and/or 2,8-oxoAde oxidation peaks.

Acetic acid- and phenyl-p-benzoquinone-induced overt pain-like behavior depends on spinal activation of MAP kinases, PI3K and microglia in mice

Pavao-de-Souza, Gabriela F.; Zarpelon, Ana C.; Tedeschi, Giovana C.; Mizokami, Sandra S.; Sanson, Joice S.; Cunha, Thiago M.; Ferreira, Sergio H.; Cunha, Fernando Q.; Casagrande, Rubia; Verri, Waldiceu A., Jr.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD Publicador: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD
Tipo: Artigo de Revista Científica
ENG
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The acetic acid and phenyl-p-benzoquinone are easy and fast screening models to access the activity of novel candidates as analgesic drugs and their mechanisms. These models induce a characteristic and quantifiable overt pain-like behavior described as writhing response or abdominal contortions. The knowledge of the mechanisms involved in the chosen model is a crucial step forward demonstrating the mechanisms that the candidate drug would inhibit because the mechanisms triggered in that model will be addressed. Herein, it was investigated the role of spinal mitogen-activated protein (MAP) kinases ERK (extracellular signal-regulated kinase), JNK (Jun N-terminal Kinase) and p38, PI3K (phosphatidylinositol 3-kinase) and microglia in the writhing response induced by acetic acid and phenyl-p-benzoquinone, and flinch induced by formalin in mice. Acetic acid and phenyl-p-benzoquinone induced significant writhing response over 20 min. The nociceptive response in these models were significantly and in a dose-dependent manner reduced by intrathecal pre-treatment with ERK (PD98059), JNK (SB600125), p38 (SB202190) or PI3K (wortmannin) inhibitors. Furthermore, the co-treatment with MAP kinase and PI3K inhibitors, at doses that were ineffective as single treatment...

"Determinação da estrutura cristalina e molecular de três 3-fenil-2-izoxazolin-5-ona-4-benzilideno substituído"; "Crystalline and molecular structure of three substituted 3-phenyl-2-izoxalin-5-one-4-benzilidenes"

Napolitano, Helena Cristina Assunção Santana
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 31/03/2006 PT
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Foram determinadas as estruturas cristalinas de três 3-fenil-2- izoxazolin-5-ona-4-benzilideno substituídas com potencial atividade antiinflamatória, a partir dos dados difratométricos de raios-X, usando os Métodos Diretos. O refinamento foi obtido pelo método dos Mínimos Quadrados. O composto C16H11NO2 cristalizou no sistema cristalino monoclínico, grupo espacial P21/a, a = 11,786(5) Å, b = 5,745(1) Å, c = 17,862(5) Å, ß = 95,988(5)º, Z = 4, V = 1202,8(12) Å3 . O composto C17H13NO3 cristalizou no sistema cristalino ortorrômbico, grupo espacial Pna21, a = 11,652(5) Å, b = 6,000(5) Å, c = 19,542(5) Å, Z = 4, V = 1366,2(13) Å3. O composto C17H13NO4 cristalizou no sistema cristalino ortorrômbico, grupo espacial Pcab, a = 10,6983(9) Å, b = 12,6111(8) Å, c = 20,926(2) Å, Z = 8, V = 2823,3(4) Å3. Em todas as estruturas verificou-se semelhança estrutural para com a fenilbutazona.; The crystal structures of three substituted 3-phenyl-2- isoxazolin-5-one-4-benzilidene with potential biological activities have been determined from diffractometric X ray data using the Direct Method. The refinement has been obtained through the least squares method. The compound C16H11NO2 crystallized in the monoclinic crystal system, space group P21/a...

The cathodic deprotection of the nitrobenzoyl group from phenyl nitrobenzoates in N,N-dimethylformamide

Jorge, SMA; Stradiotto, N. R.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 237-241
ENG
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The reduction of phenyl benzoates with nitro substituents at the 2-,3- and 4-positions of the benzoates in N,N-dimethylformamide is reported. The phenyl 4- and 3-nitrobenzoate are reduced in two cathodic steps. The first one, at about -0.9 V vs. SCE, a reversible one-electron process, gives a rather stable anion radical. The second reduction step at potentials between -1.5 and -2.0 V vs. SCE leads to formation of the dianion, which decomposes giving free phenol in good yields (> 80%). on the other hand, the phenyl 2-nitrobenzoate is reduced in one cathodic step. This step occurs at -0.9 V with formation of an unstable anion radical which decomposes via C-O bond cleavage, giving phenol with a yield of ca. 80%. The mechanisms of the reduction of these compounds are discussed. (C) 1997 Elsevier B.V. S.A.

Preparação e caracterização de fases estacionarias de dimetil-metil-fenil siloxano sobre silica para cromatografia liquida de alta eficiencia; Preparation and characterization of stationary phases of copolymer of dimethyl-methyl-phenyl siloxane on the silica for high porformance liquid

Josimara Lourenço
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 23/11/2005 PT
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Em cromatografia líquida de alta eficiência (CLAE), a coluna é freqüentemente considerada como o "coração do sistema cromatográfico", pois é nela que ocorre a separação. Dessa forma, a busca por fases estacionárias capazes de realizar separações com alta eficiência e desempenho tem sido uma constante em muitos laboratórios de pesquisa. Polissiloxanos fenil substituídos têm sido extensivamente utilizados em cromatografia gasosa, mas a sua aplicação em CLAE tem despertado pouca atenção. Neste trabalho foram preparadas fases estacionárias para CLAE, com grupos fenil, a partir da sorção e subseqüente imobilização por tratamento térmico do copolímero de dimetil(52-48%)-metil-fenil(48-52%) siloxano sobre a sílica (Kromasil, 5 mm). Medidas da quantidade de carbono, volume de poro, área superficial específica, espectroscopia no infravermelho e RMN de C e Si foram realizadas para caracterizar físico-quimicamente as fases estacionárias. Também foram feitas avaliações cromatográficas utilizando misturas teste de compostos orgânicos de diferentes polaridades. As fases estacionárias preparadas a partir do copolímero de dimetil(52-48%)-metil-fenil(48-52%) siloxano sobre a sílica e imobilizadas termicamente a 150 °C...

Purificação de fragmentos Fab a partir de solução de clivagem enzimática de IgG humana : cromatografia de pseudoafinidade com quelatos metálicos e fenil boronato como ligantes; Fab fragments purification from enzymatic cleavage of human IgG : pseudo affinity chromatography using chelated metals and phenyl boronate as binding

Luana Cristina Andrade da Silva
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 10/11/2014 PT
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As imunoglobulinas do tipo G humana (IgG) são amplamente empregadas em tratamentos terapêuticos contra câncer, doenças auto-imunes e imunodeficiência adquirida e na área analítica, em testes diagnósticos. Os fragmentos Fab podem ser obtidos por clivagem enzimática da molécula de IgG nativa ou por tecnologia de DNA recombinante. O fragmento Fab é composto por regiões constantes e variáveis, sendo que as regiões variáveis de cadeias leve e pesada compõem o fragmento Fv. Tanto os fragmentos Fab quanto os fragmentos Fv foram citados como segunda e terceira geração de anticorpos, respectivamente, e têm sido crescente o interesse em empregá-los em tratamentos terapêuticos, visto que ambos possuem menor massa molar em relação a IgG intacta e preservam a capacidade de se ligar ao antígeno. Como a utilização destas proteínas nas áreas terapêutica e analítica requer um alto grau de pureza, estratégias de purificação vêm sendo desenvolvidas. No intuito de contribuir para o desenvolvimento de processos de purificação de fragmento Fab, estudou-se o emprego de ligantes alternativos aos bioespecíficos proteínas A, G e L, comumente empregados para este fim. Neste trabalho, a purificação dos fragmentos Fab foi realizada por cromatografia de afinidade com íons metálicos imobilizados (IMAC) e fenil boronato (FB). Quanto a IMAC...

Antibacterial activity of phenyl isothiocyanate on Escherichia coli and Staphylococcus aureus

Abreu, Ana C.; Borges, Anabela; Simões, Lúcia C.; Saavedra, Maria J.; Simões, M.
Fonte: Bentham Science Publishers; Bentham Science Publishers Publicador: Bentham Science Publishers; Bentham Science Publishers
Tipo: Artigo de Revista Científica
Publicado em //2013 ENG
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The present study has been aimed to assess the antibacterial effects of the glucosinolate hydrolysis product phenyl isothiocyanate (PITC) against Escherichia coli and Staphylococcus aureus. Aspects on the antibacterial mode of action of PITC have also been characterized, such as the changes on surface physicochemical characteristics and membrane damage. The minimum inhibitory concentration of PITC was 1000 µg/mL, for both bacteria. The antimicrobial potential of PITC was compared with selected antibiotics (ciprofloxacin, erythromycin, streptomycin, tetracycline and spectinomycin),that reported a moderate effect. The combination of PITC with ciprofloxacin and erythromycin against S.aureus exhibited a good antimicrobial efficacy, due to an additive effect (the diameter of inhibition zones increased from 30 to 40 mm for ciprofloxacin and almost the double for erythromycin). The other combinations reported unsatisfactory results against both bacteria. The study of the physiological changes induced by PITC action demonstrated the interaction between the electrophilic compound and the bacterial cells at several points that causes changes in membrane properties (decreases negative surface charge, increases surface hydrophilicity and electron donor characteristics). PITC was also found to disturb membrane function...

3-phenyl-4-acyl-5-isoxazolones as reagents for liquid-liquid extraction of tetravalent zirconium and hafnium from acidic chloride solutions

Reddy,B. Ramachandra; Kumar,J. Rajesh; Reddy,A. Varada
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2006 EN
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Liquid liquid extraction of tetravalent zirconium and hafnium from acidic chloride solutions has been investigated using 3-phenyl-4-acyl-5-isoxazolones in xylene such as 3-phenyl-4-benzoyl-5-isoxazolones (HPBI), 3-phenyl-4-(4-fluorobenzoyl)-5-isoxazolone (HFBPI) and 3-phenyl-4-(4-toluoyl)-5-isoxazolone (HTPI). The extraction of zirconium(IV) / hafnium(IV) shows a ion exchange mechanism: MO2+ (aq) + 2 HA (org) « MOA2 (org) + 2 H+(aq), where M = Zr(IV) / Hf(IV) and HA = HPBI or HFBPI or HTPI. The variation of the D ([MOA2] (org) / [MO2+](aq); ratio of the possible extraction equilibrium species) values with an increase of the acid / extractant concentration showed a linear plot with a slope of 2. The effect of the nature of the diluents like carbon tetrachloride, cyclohexane, n-hexane, benzene, nitrobenzene, xylene, toluene and chloroform on the extraction of zirconium(IV) / hafnium(IV) has been studied. The extraction behavior of zirconium(IV) / hafnium(IV) was also compared with that of other metal ions like titanium(IV), aluminium(III) and iron(III), which can be generally associated with the metal ions studied.

Enantioselective hydrogenation of ethyl pyruvate and 1-phenyl-1,2-propanedione on catalysts prepared by impregnation of colloidal platinum on SiO2

Ruiz,Doris P.; Fierro,José L. G.; Reyes,Patricio A.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 EN
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The enantioselective hydrogenation of ethyl pyruvate and 1-phenyl-1,2-propanedione was studied at 298 K and 40 bar of H2 over colloidal Pt stabilized with cinchonidine (CD) and supported on silica. The catalysts were prepared by impregnation of colloidal Pt on SiO2, leading to a metal load close to 1 wt.%. The colloid was prepared from an aqueous solution of H2PtCl6 and stabilized with different quantities of CD. The catalysts were characterized by nitrogen adsorption-desorption isotherms at 77 K, XPS, XRD and TEM techniques. The reactions were carried out in a stainless steel batch reactor using cyclohexane as solvent and cinchonidine as chiral modifier. The addition of CD to the catalysts allows the stabilization and control of the platinum particle size and also affects the enantiomeric excess (ee) of the system, affording a higher proportion of the (R)-product. The relationship between the enantioselectivity and the CD concentration (added in situ) exhibits a bell type curve for both reactions, this being indicative of the importance of a competitive adsorption of the modifier and substrate on the catalyst surface.

Production of allyl phenyl carbinol (APC) by biotrans-formation using Rhizopus arrhizus

Shukla,Vilas B.; Kulkarni,Pushpa R.
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2000 EN
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The objective of the present work was to study the stereoselective synthesis of homo-allylic alcohol using stereoselective hydrolysis by Rhizopus arrhizus and also to study the stereoselective synthesis of allyl phenyl carbinol (APC) or 1-Phenyl-3-butene-1-o by combination of chemical synthesis and biotransformation from cheap raw materials such as benzaldehyde and allyl bromide. Stereospecific synthesis of allyl phenyl carbinol (APC) was achieved by acetate hydrolysis by R. arrhizus giving R (+) enantiomer. Maximum enantiomeric excess of APC was obtained at 16 h where as maximum yield of it was obtained at 48 h of biotransformation.

The synthesis, characterization and structures of some 4-[((E)-1-{2-hydroxy-5-[(E)-2-(aryl)-1-diazenyl]phenyl}methylidene)amino]benzoic acid

Basu Baul, T.; Das, P.; Chandra, A.; Mitra, S.; Pyke, S.
Fonte: Elsevier Sci Ltd Publicador: Elsevier Sci Ltd
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
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The structures of several azo-benzoic acids, 4-[((E)-1-{2-hydroxy-5-[(E)-2-(aryl)-1-diazenyl]phenyl}methylidene)amino]benzoic acid along with their precursors 2-hydroxy-5-[(E)-(aryldiazenyl)]benzaldehydes were confirmed using 1H, 13C NMR, UV–VIS and IR spectroscopic techniques. UV–VIS absorption spectra were measured in pure organic solvents while complementary spectroscopic experiments using mixed solvent systems as well as in the presence of base were undertaken to characterize the different species present in solution. Both acid–base dissociation and azo–hydrazone tautomerism occurred in solution, with the extent of the individual equilibria being dependent on the solvent composition and/or pH of the medium. Molecular structures and geometries were optimized using the B3LYP density functional theory method employing the 6-31G(d) basis set.; Tushar S. Basu Baul, Pradip Das, Asit K. Chandra, Sivprasad Mitra and Simon M. Pyke

Voltammetric Behavior of a Chemically Modified Silsesquioxane with 4-Amino-5-Phenyl-4h-[1,2,4]-Triazole-3-Thiol and its Application for Detection of L-Dopamine

Silvestrini, Daniela Rodrigues; Serantoni da Silveira, Tayla Fernanda; Bicalho, Urquisa de Oliveira; Carmo, Devaney Ribeiro do
Fonte: Esg Publicador: Esg
Tipo: Artigo de Revista Científica Formato: 2839-2858
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 2012/11306-0; Processo FAPESP: 2012/05438-1; Processo FAPESP: 2013/08495-9; A hybrid nanocomposite formed by interaction of a octakis(3-chloropropyl) octasilsesquioxane (SS) modified with 4-Amino-5-Phenyl-4H-1,2,4-Triazole-3-Thiol (APhTT), and its subsequent reaction with copper and hexacyanoferrate (III) (CuHSA) was incorporated into a graphite paste electrode and the electrochemical studies were conducted with cyclic voltammetry. The cyclic voltammogram of the graphite paste electrode modified with CuHSA, showed one redox couple with average potential E-theta = 0.71V (vs Ag/AgCl(sat.)), attributed to the (CuFeII)-Fe-II(CN)(6)/(CuFeIII)-Fe-II(CN)(6) process (20% w/w; v= 20 mV s(-1); KCl; 1.00 mol L-1) The graphite paste electrode modified with CuHSA allowed the electrocatalytic determination of L-Dopamine using electrochemical techniques such as, cyclic voltammetry and differential pulse voltammetry. Through differential pulse voltammetry was possible to evidence two linear regions in the studied concentration range and the detection limit obtained by this technique was lower than that obtained by the technique of cyclic voltammetry.

Effect of the nature of the support on the enantioselective hydrogenation of 1-phenyl-1,2-propanedione over supported iridium catalysts

Marzialetti, Teresita; Reyes, P.; García Fierro, José Luis
Fonte: Sociedad Chilena de Química Publicador: Sociedad Chilena de Química
Tipo: Artículo
ENG
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The enantioselective hydrogenation of 1-phenyl-1,2-propanedione at 298 K and 40 bar over modified supported iridium catalysts has been studied. Cinchonidine has been used as chiral inducer. The catalysts were obtained by impregnation of Ir(acac)3 on three different supports: SiO2, TiO2 and MoO3, followed by calcination in air and reduction under hydrogen at 773 K. All the solids were characterized by nitrogen adsorption-desorption isotherms at 77 K, H2 chemisorption, XRD, TEM, TPR and XPS. It was found that Ir/SiO2 and Ir/TiO2 catalysts reduced at high temperatures, 773 K, possess similar metal particle size, close to 2.0 nm, eventhough the H/Ir ratio obtained from H2 chemisorption showed larger differences, with the H/Ir ratio being lower for titania- and molybdenum-supported iridium catalysts. In these samples, migration of the partially reduced supports, TiOx and MoOx moieties, on the metal crystals induce the creation of Ird+ species. TPR and XPS results confirmed that the metal component was not completely reduced. The activity was influenced by the nature of the support, being more active those in the SMSI state such as Ir/TiO2 and Ir/MoO3 being more active. This has been attributed to the presence of electron deficient metal species...

Optical properties of an ormosil system comprising methyl- and phenyl-substituted silica

Atkins, Graham; Krolikowska, Maryla; Samoc, Anna
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
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We report an organically modified silica (ormosil) system in which the refractive index can be varied from 1.40 to 1.55 by modifying the silica backbone with phenyl and methyl groups, which increase and decrease the refractive index, respectively. By changing the quantities of the phenyl- and methyl-modified precursors in the sol-gel mixture, the refractive index can be varied while keeping the organic fraction of the material constant. Crack-free, dried films up to 15-μm thick have been coated onto silicon and glass substrates, with potential application to optical waveguides for planar integrated circuits. The contributions of SiO-H and C-H absorptions to the attenuation in the communications windows are discussed, along with factors affecting the homogeneity and cracking tendency of the ormosils.

Competition between and π- and σ-based interactions in metal ion complexes of the phenyl radical

Petrie, Simon
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
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Hybrid density functional theory (B3-LYP and B3-PW91) and counterpoise-corrected ab initio (MP2) calculations have been performed for the adducts of the main-group metal ions Na+, Mg+, Al+, K+, and Ca+ with the phenyl radical C6H5. While the calculated bond dissociation energies (BDEs) and complexation geometries of the alkali metal ion adducts do not differ substantially from those determined for the analogous M+/benzene π-complexes, the alkaline earth ions exhibit a strong preference for σ-bond formation at the bare C atom of the phenyl ring, with calculated BDEs exceeding those determined for benzene complexation by approximately 80 and 150kJmol-1 for Mg+ and Ca+, respectively. This σ-coordination is only feasible when the unpaired spins on the reactant Mg+ (or Ca+) and C6H5 radicals are opposed, thereby leading to a closed-shell (singlet state) adduct ion. When the unpaired spins are aligned, the triplet-state adduct thus produced adopts π-complex minimum energy geometry with a BDE significantly below that of the corresponding M+/benzene complex. Both π- and σ-coordination are also found to be local minima on the AlC6H5+ potential energy surface, with the BDE of the Al+/C6H5 σ-complex being approximately 50kJmol-1 larger than that of the corresponding π-complex...

Cell survival patterns in the pedunculopontine tegmental nucleus of methyl-4-phenyl-1,2,3,6-tetrarahydropyridine-treated monkeys and 60HDA-lesioned rats: evidence for diffences to idiopathic Parkinson disease patients

Heise, Claire E; Teo, Zui Chih; Wallace, Bradley A; Ashkan, Keyoumars; Benabid, Alim-Louis; Mitrofanis, John
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
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We explore the patterns of cell loss in the pedunculopontine tegmental nucleus (PpT), a major locomotor and muscle tone suppression centre of the brainstem, in two animal models of Parkinson disease, namely MPTP (methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-treated monkeys and 6-hydroxydopamine(6OHDA)-lesioned rats. Although there have been many studies documenting the loss of dopaminergic cells from the substantia nigra in these animal models, there has been little, if any, documentation of a loss of cells in the PpT. Results were obtained from macaque monkeys (Macaca fascicularis) and Sprague-Dawley rats. For the monkey series, animals were injected intramuscularly with MPTP (0.2 mg/kg) for 8 days consecutively and then allowed to survive for 21 days thereafter. Each monkey underwent behavioural assessment for parkinsonian symptoms. For the rat series, 6OHDA was injected into the midbrain using stereotactic coordinates. Rats were then allowed to survive for either 7, 14, 28, or 84 days thereafter. Monkey and rat brains were aldehyde-fixed and processed for routine tyrosine hydroxylase (TH; to label nigral dopaminergic cells) and nitric oxide synthase (NOs; to label PpT cholinergic cells) immunocytochemistry. In monkeys, the morphology...

IN VITRO PRODUCTION OF LEISHMANICIDAL ALKALOID 2 PHENYL-QUINOLINE BY ANGOSTURA LONGIFLORA KRAUSE A

Guarachi,Marina; Paz,Magaly; Chuqui,Rogelio; Sauvain,Michel; Flores,Ninoska; Alvarez,Ma Teresa; Giménez,Alberto
Fonte: Revista Boliviana de Química Publicador: Revista Boliviana de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2008 EN
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Angostura longiflora (K.) Kallunki (Rutaceae) is a medicinal wood tree used by Amazonian tribes for the treatment of stomach parasites and leishmaniasis. Cell cultures from leaves of this species were obtained on Murashige and Skoog (MS) medium supplemented with kinetine (kin) and 2,4-dichlorophenoxyacetic acid (2,4-D) based on a factorial design, where concentrations of sucrose and phosphate were changed. The increasing of sucrose and phosphate enhanced the specific growth rate from 0.16 to 0.33d-1. The leishmanicidal alkaloid, 2-phenyl-quinoline was isolated from calli and identified by means of nuclear magnetic resonance (NMR) and mass (EI) spectra. This is the first report concerning the production, isolation and chemical characterization by NMR and mass spectra of the main alkaloid, in Evanta leaves, 2-phenyl-quinoline from cell cultures of A. longiflora

A Rapid, One-pot, Multi-component Route to 4,4'-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols)

Hassankhani,Asadollah
Fonte: Sociedad Química de México A.C. Publicador: Sociedad Química de México A.C.
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
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A new, efficient and environmentally benign protocol for the one-pot, multicomponent synthesis of 4,4'-arylmethylene-bis(3-methyl1-phenyl-1H-pyrazol-5-ols) by condensation of aryl aldehydes, phenyl hydrazine and ethyl acetoacetate catalyzed by Ce(SO4)2.4H2O as an ecofriendly catalyst with high catalytic activity and reusability at 125 °C under solvent-free conditions is reported. The reaction proceeds to completion within 5-12 min in 81-98% yield. This new green methodology is of interest due to minimizing the cost of operational hazards and environmental pollution, its excellent yields, short reaction time and high catalyst activity and reusability.

Preparation of (+)- and (-)- β-phenyl- and β-(4-chlorophenyl)-γ-butyrolactones: Key Intermediates in the Synthesis of β-phenyl-GABA and Baclofen

Gómez-Gutiérrez,Jazmín; Meléndez-Rodríguez,Myriam; Suárez-Castillo,Óscar R.; Castelán-Duarte,Luis E.; Fragoso-Vázquez,Manuel J.; López-Vázquez,Erick; Sánchez-Zavala,Maricruz
Fonte: Sociedad Química de México A.C. Publicador: Sociedad Química de México A.C.
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
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The preparation of β-phenyl- and β-(4-chlorophenyl)-γ-butyrolactones ( ± )-3 and ( ± )-4 and their resolution to the corresponding (+)-(S)-3, (-)-(R)-3 and (+)-(S)-4, (-)-(R)-4 through formation, flash column chromatography separation and subsequent hydrolysis of diastereoisomeric 4-hydroxybutyramides (2'R,3S)-5, (2'R,3R)-5, (2'R,3S)-6 and (2'R,3R)-6 is described. The absolute configuration assignment of enantiopure 3 and 4 was supported by X-ray crystallographic structures of (2'R,3R)-5, (2'R,3S)-6 and (2'R,3R)-6.