Browsing by Author "Núñez Vergara, Luis"
Now showing items 81-100 of 106
-
Núñez Vergara, Luis; Squella Serrano, Juan; Silva, Luis J. (1982)2-Hydroxy-3-phenyl-6-methylpyrazine is identified as the product obtained by acidic degradation of cephalexin in the presence of formaldehyde. In 5M hydrochloric acid this product gives a well-defined reduction wave with ...
-
Squella Serrano, Juan; Becerra, Rebeca; Núñez Vergara, Luis (1987)
-
Núñez Vergara, Luis; Guinez-Castro, Luis; Bollo Dragnic, Soledad; Squella Serrano, Juan (1996)The reactivity of the electrochemically generated nitro radical anion from nicardipine, nitrendipine and nimodipine, all nitro aryl 1,4-dihydropyridine derivative, with relevant thiols, was quantitatively assessed by cyclic ...
-
Squella Serrano, Juan; Letelier, M.; Lindermeyer, L.; Núñez Vergara, Luis (Elsevier Ireland Ltd, 1996)The electrochemical properties of nifuroxazide have been investigated in aqueous and aqueous-DMF mixed solvents. In aqueous media, a single, irreversible four-electron reduction occurs to give the hydroxylamine derivative. ...
-
A selective voltammetric method to follow the hydrolytic degradation of nitrendipine and nisoldipine Álvarez Lueje, Alejandro; Sturm Schaub, Juan; Núñez Vergara, Luis; Squella Serrano, Juan (WILEY-V C H VERLAG GMBH, 2001-12)The development and application of a differential pulse voltammetric procedure for the hydrolytic degradation kinetic study of two well-known 1,4-dihydropyridine type drugs, nitrendipine and nisoldipine are presented. The ...
-
Pérez Cruz, Karina Angélica (Universidad de Chile, 2016)Las cumarinas (2H-1-benzopiran-2-ona) son estructuras químicas presentes en especies vegetales ampliamente distribuidas en la naturaleza con una reconocida actividad biológica, entre las que destacan sus propiedades ...
-
López Alarcón, Camilo; Squella Serrano, Juan; Miranda, Dante; Núñez Vergara, Luis (WILEY-V C H VERLAG GMBH, 2004-04)Spectroelectrochemical and HPLC characterization of the electrochemical oxidation in aqueous medium of a series of six N-1 and C-4 substituted 1,4-dihydropyridines is presented. Based on the analysis of spectra obtained ...
-
Yáñez, C.; Salazar, R.; Núñez Vergara, Luis; Squella Serrano, Juan (2004)Inclusion complexation between furnidipine (2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-tetrahydrofurfuryl 5-methyl diester), a calcium-channel antagonist, and beta-cyclodextrin (beta-CyD) ...
-
García, Cristóbal; Cabezas, Karina; Nonell, Santi; Núñez Vergara, Luis; Morales Valenzuela, Javier; Günther Sapunar, Germán; Pizarro Urzúa, Nancy Alejandra (The American Society of Photobiology, 2014)The electronic nature of substituents attached to the 4-aryl moiety of 1,4-dihydropyridines strongly affects the photophysical and photochemical behavior of these family of compounds. The presence of an electron donor ...
-
Pardo Jiménez, Viviana Gladys; Barrientos, C.; Pérez Cruz, Karina Angélica; Navarrete Encina, Patricio; Olea Azar, Claudio; Núñez Vergara, Luis; Squella Serrano, Juan (2014)In this paper, a series of six dihydropyridine-fused coumarins were synthesized and electrochemically characterized in dimethylformamide (DMF). Dihydropyridine ring oxidation on glassy carbon electrode (GCE) for condensed ...
-
Soulère, Laurent; Sturm, Juan Carlos; Núñez Vergara, Luis; Hoffmann, Pascal; Périé, Jacques (2001)A series of S-nitrosothiol compounds, structurally related to the NO-donor S-nitroso-N-acetyl-D,L-penicillamine (SNAP) that contain amidin groups were synthesised by S-nitrosation of the corresponding thiols and characterised. ...
-
Systematic HPLC study of a new series of 4-methyl-1,4-dihydropyridines with antitrombotic activity Núñez Vergara, Luis; Álvarez Lueje, Alejandro; Sturm,; Sunkel,; Squella Serrano, Juan (Marcel Dekker Inc., 1998)A systematic study of a new series of 4-methyl-1,4-dihydropyridine derivatives by HPLC by both photodiode array and electrochemical detectors is reported. The optimum mobile phase was acetonitrile/0.05 M phosphate buffer ...
-
Mozo, J. D.; Carbajo, J.; Sturm, J. C.; Núñez Vergara, Luis; Moscoso Cabello, Raúl Andrés; Squella Serrano, Juan (2011)Cyclic voltammetry (CV) is a very useful electrochemical tool used to study reaction systems that include chemical steps that are coupled to electron transfers. This type of system generally involves the chemical reaction ...
-
Maya Arango, Juan; Morello Casté, Antonio; Repetto Scaramelli, Yolanda; Rodríguez, Andrés; Puebla, P.; Caballero S., Esther; Medarde, M.; Núñez Vergara, Luis; Squella Serrano, Juan; Ortíz Yáñez, María Eugenia; Fuentealba, J.; San Feliciano, Arturo (ACADEMIC PRESS INC, 2001-09)Chagas' disease constitutes a therapeutic challenge because presently available drugs have wide toxicity to the host and are generally ineffective in the chronic stages of the disease. A series of oxazolo(thiazolo)pyridene ...
-
Argüello da Silva, Jacqueline; Barría, Claudio Saitz; Jullian Matthaei, Carolina; Navarrete, Patricio; Núñez Vergara, Luis; Squella Serrano, Juan (2005)1,4-dihydropyridine derivatives constitute an important pharmacological group for the treatment of cardiovascular diseases. We have synthesised a series 4-(5′-nitro-2′-furyl)-1,4-dihydropyridine derivatives, which were ...
-
Santander,; Núñez Vergara, Luis; Sturm,; Squella Serrano, Juan (2001)Melatonin and Vitamin B6 can be oxidized at the glassy carbon electrode showing well-resolved anodic peaks by differential pulse voltammetry. Vitamin B6 shows an oxidation peak potential of about 650 mV vs Ag/AgCI in ammonia ...
-
Núñez Vergara, Luis; Squella Serrano, Juan; Patriarche, G. J. (1986)Trazodone, a triazolopyridine derivative with antidepressant activity, is irreversibly oxidized in two steps in a large range of scan rates. The first peak shows a linear dependence on trazodone concentration. This behaviour ...
-
Álvarez Lueje, Alejandro; Núñez Vergara, Luis; Squella Serrano, Juan (1994)The anodic electrochemical behavior of the five members of the 1,4‐dihydropyridine calcium antagonists family was studied. In all of the studied compounds (nifedipine, nitrendipine, nimodipine, nicardipine, and furaldipine), ...
-
Voltammetric behavior of zaleplon and its differential pulse polarographic determination in capsules Larenas Gutiérrez, Gipsy; Bollo Dragnic, Soledad; Rodríguez, M.; Lemus Gutiérrez, Igor; Núñez Vergara, Luis; Squella Serrano, Juan; Álvarez Lueje, Alejandro (AOAC INTERNATIONAL, 2005-07)In this work both the electrochemical behavior and the analysis of the hypnotic pyrazolopyrimidine derivative zaleplon were studied. Zaleplon in ethanol-0.1 M Britton Robinson buffer solution (30-70) showed 2 irreversible, ...
-
Squella Serrano, Juan; Lemus, I.; Sturm, J. C.; Núñez Vergara, Luis (Taylor and Francis Inc., 1997)Ketorolac is an antiinflammatory-analgesic agent that is oxidizable at the glassy carbon electrode. The voltammetric oxidation produces two well resolved pH-dependent peaks, that are overlapped at pH>10. Using this ...