Browsing by Author "201-0010569"
Now showing items 1-20 of 103
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Valenzuela, V.; Santander, P.; Camargo Grandón, Rodrigo; Squella Serrano, Juan; López Alarcón, Camilo; Núñez Vergara, Luis (TAYLOR & FRANCIS, 2004-07)In the present paper, a direct quenching of radical species by a number of synthesized nitrosoaryl 1,4-dihydropyridines and their parent nitroaryl 1,4-dihydropyridines was determined in aqueous media at pH 7.4. These two ...
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Ramírez, Eduardo Alejandro; Zon, María Alicia; Jara Ulloa, Paola Andrea; Squella Serrano, Juan; Núñez Vergara, Luis; Fernández, Héctor (PERGAMON-ELSEVIER SCIENCE LTD, 2010-01-01)We study the thermodynamics and kinetics of the adsorption of a redox couple having quinone nature on glassy carbon electrodes. This couple is produced by the anodic oxidation of mycotoxin ochratoxin A in 10% acetonitrile ...
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Núñez Vergara, Luis; Daza, R.; Zanocco, A.; Squella Serrano, Juan (1983)2-Hydroxy-3-(p-hydroxyphenyl)-6-methylpyrazine (HHMP) is identified as the product obtained by acidic degradation of amoxycillin in the presence of formaldehyde. I.R., n.m.r. and elemental analysis data are reported. The ...
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Núñez Vergara, Luis; Navarrete Encina, Patricio; Salas, S.; Conde, B.; Carbajo, J.; Squella Serrano, Juan; Camargo Grandón, Rodrigo (PERGAMON-ELSEVIER SCIENCE, 2007-05-09)El mass spectra of products of the dihydropyridine Hantzsch synthesis using hydroxy and methoxy aldehydes as starting materials are reported. The reaction products (C-4 hydroxy- and methoxyphenyl-1,4-dihydropyridines and ...
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Díaz Araya, Guillermo; Godoy Oviedo, Luis; Naranjo, Luis; Squella Serrano, Juan; Letelier Muñoz, María Eugenia; Núñez Vergara, Luis (PERGAMON-ELSEVIER SCIENCE, 1998-09)1. Lipid peroxidation in rat brain slices was induced by Fe+3/ascorbate. 2. Brain lipid peroxidation, as measured by malondialdehyde formation, was inhibited by all the tested nitro aryl 1,4-dihydropyridine derivatives ...
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Álvarez Lueje, Alejandro; Pastine Sepúlveda, Javiera; Squella Serrano, Juan; Núñez Vergara, Luis (SOCIEDAD CHILENA DE QUIMICA, 2005-12)In this work an HPLC stability-indicating method was developed and applied to study the hydrolytic behaviour of lovastatin in different simulated fluids. The selected chromatographic conditions were a C-18 column, ...
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López Menadier, Marcelo Leonardo (Universidad de Chile, 2006)En esta Memoria se estudió la reactividad de tres nuevas 1,4-dihidropiridinas (1,4-DHP) frente al anión radical superóxido (O2 .-), y se evaluó la influencia de los sustituyentes en posición 4 del anillo dihidropiridí ...
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Morales Montecinos, Juan Pablo (Universidad de ChilePrograma Cybertesis, 2007)En la presente memoria se reporta la caracterización electroquímica y la reactividad con radicales libres, alquilo y alquilperoxilo ABAP-derivados de tres nuevas 1,4 dihidropiridinas C4-substituidas (3,4,5-trihidroxifenil-DHP, ...
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Cyclic voltammetric and EPR spectroscopic studies of benzodiazepines: Loprazolam and flunitrazepam Núñez Vergara, Luis; Bollo Dragnic, Soledad; Olea Azar, Claudio; Navarrete-Encina, Patricio; Squella Serrano, Juan (Elsevier, 1997)The present paper reports on the electrochemical characterization by cyclic voltammetry of two 1,4-benzodiazepines, loprazolam and flunitrazepam in protic, aprotic and mixed media. In protic media (ethanol + 15 mM citrate ...
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Ortíz Yáñez, María Eugenia; Núñez Vergara, Luis; Squella Serrano, Juan (ELSEVIER SCIENCE, 2002-02-08)We have studied the O-2/O-2(.-) redox couple on the HMDE in DMSO aprotic media, obtaining optimal conditions of both oxygen concentration and scan rate in order to avoid oscillatory phenomena. By choosing the oxygen ...
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Bollo Dragnic, Soledad; Núñez Vergara, Luis; Squella Serrano, Juan (ELSEVIER SCIENCE, 2004-01-15)PA-824 (2-nitro-6-(4-trifluoromethoxy-benzyloxy)-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine) is being tested as antituberculosis drug. Little is known on the action mechanism of PA-824; however the reduction of the nitro ...
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Bollo Dragnic, Soledad; Núñez Vergara, Luis; Bontá, M.; Chauviere, G.; Perie, J.; Squella Serrano, Juan (ELSEVIER SCIENCE, 2001-09-21)Megazol (2-amino-5-(1-methyl-5-nitro-2-imdazolyl)-1,3,4-thiadiazol, CAS 19622-55-0) and related nitroimidazole compounds are being tested as antichagasic drugs. Little is known on the mode of action of megazol. However, ...
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Carbajo, J.; Bollo Dragnic, Soledad; Núñez Vergara, Luis; Campero, A.; Squella Serrano, Juan (ELSEVIER SCIENCE, 2002-08-23)We have chosen 4-nitroimidazole (4-NIm) as a prototype of nitroimidazolic compounds in order to carry out an exhaustive cyclic voltammetric study in protic media, 0.1 M Britton-Robinson buffer+0.3 M KCl with ethanol as a ...
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Cyclic voltammetry and digital simulation of the electroreducction of ortho-and meta-nitro aryl ... Bollo Dragnic, Soledad; Núñez Vergara, Luis; Squella Serrano, Juan (Sociedad Chilena de Química, 1999)Cyclic voltammetry (CV) and digital simulation methods are utilezed to elucidate the mechanism of electrochemical reduction of a series of nitro aryl 1,4-dihydropyridines im protic (aqueous) and mixed media. The experimental ...
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Bollo Dragnic, Soledad; Finger Caraccioli, Sebastián; Sturm Schaub, Juan; Núñez Vergara, Luis; Squella Serrano, Juan (PERGAMON-ELSEVIER, 2007-04-20)The heterogeneous electron transfer reaction for the reduction of some nitroso aromatic derivatives in aqueous-alcoholic medium was studied on both mercury and glassy carbon electrodes (GCE) by using cyclic voltammetry ...
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Merino, M.; Núñez Vergara, Luis; Squella Serrano, Juan (SOCIEDAD CHILENA DE QUIMICA, 2000-09)Carbon paste electrodes were modified with cytochrome c reductase enzyme. The behavior of the electrodes was characterized by cyclic voltammetry. The cytochrome c reduction was investigated both on the enzyme modified ...
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Fuente Salvat, Elizabeth de la (Universidad de ChilePrograma Cybertesis, 2007)
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Verschae Tannenbaum, Marcela Teresa (Universidad de Chile, 2005)En el ámbito del control de doping es importante poder detectar y cuantificar con un nivel de confianza adecuado los compuestos incluidos en la lista de sustancias prohibidas de la Agencia Mundial Antidopaje (WADA) que ...
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Yáñez Soto, Claudia; Núñez Vergara, Luis; Squella Serrano, Juan (WILEY-V C H VERLAG GMBH, 2002-04)Carbon paste electrodes modified with beta-cyclodextrin have been investigated for voltammetric determination of nitrendipine. The immobilization of the beta-cyclodextrin on the carbon paste leads to a modification of the ...
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Álvarez Lueje, Alejandro; Pujol, Silvina; Núñez Vergara, Luis; Squella Serrano, Juan (AOAC INTERNATIONAL, 2002-11)Lercanidipine in ethanol-0.04M Britton-Robinson buffer (20 + 80) gives an irreversible anodic response on a glassy carbon electrode in a broad pH range (2-12) that depends on pH. This signal can be attributed to oxidation ...