Facultad de Ciencias Químicas y Farmacéuticas: Recent submissions

Now showing items 4201-4220 of 5085

    • Induced distant cotton effects in an aromatic chromophore in mixed aminoacides of copper(II) 
      Bunel Torrealba, Sergio; Ibarra, Carmen; Urbina, A.; Bunton, Clifford A. (Pergamon Press, 1977)
      Chiral amino acids bonded to copper(II) induce Cotton effects in the visible and UV regions corresponding tod-d and charge transfer transitions [1,2] but and induced Cotton effect on a distant ligand has not been observed ...
    • Charge transfer circular dichroism of complexes of copper(II) with aminoacids and heterocyclic ligands 
      Bunel Torrealba, Sergio; Ibarra, Carmen; Bunton, Clifford A. (Pergamon Press, 1975)
      In the u.v. region the C.D. spectra of mixed complexes of Cu(II), aminoacids and heterocyclic ligands depend upon the nature of the heterocyclic ligand, and work on the Cotton effects of bis-Ł-aminoacidates of cu(II) in ...
    • Complexation of mannosamine with cobalt(III) bis-phenanthroline. Isolation of a stable triiodide salt 
      Bunel Torrealba, Sergio; Ibarra, Carmen; Moraga, Exequiel; Parada Aliste, José; Blasko, Andrei; Bunton, Clifford A. (Sociedad Chilena de Química, 1997)
      D-β-Mannosamine reacts with cobalt(III) bis-phenanthroline to form a single 1:1 complex with the ∆ configuration at Co(III) which can be isolated as the stable triiodide salt.
    • Mixed complexes of cobalt(III) with D-glucosamine and phenanthroline 
      Blasko, Andrei; Bunton, Clifford A.; Bunel Torrealba, Sergio; Moraga, Exequiel; Ibarra, Carmen; Parada Aliste, José (Sociedad Chilena de Química, 1995)
      Examination of 1H chemical shifts of a complex of D-glucosamine with bis-phenanthroline cobalt(III)shows that the dominant ∆-complex is formed from α-D-glucosamine. A molecular mechanics simulation of the structure of ...
    • Voltammetric behaviour of nitrofurazone, furazolidone and other nitro derivatives of biological importance 
      Morales, A.; Richter Duk, Pablo; Toral Ponce, María (Royal Society of Chemistry, 1987)
      In piridine - formic acid buffer and tetramethylammonium chloride solution of pH 4.5 at a dropping mercury or a glassy carbon electrode, nitrofurazone, furazolidone and nitrofurantoin are reduced in a single six-electron ...
    • Study of procedure for the obtainment of methylcellulose from mechanic pulp in homogeneous media 
      Tapia Villanueva, Cristián; Sapag Hagar, Jaime; Siches, Pedro; Valenzuela Lozano, Fernando; Basualto Flores, Carlos (Universidad Nacional del Sur y Consejo de Investigaciones Científicas y Técnicas, 1996)
      The etherification reaction of mechanic pulp (MP) with dimethylsulphate (DMS) in homogeneous media was studied using a 2 5-1 fractional factional experimental design. In according to this model the quantity of DMS/2 g ...
    • PURIFICATION AND CHARACTERIZATION OF 2 ISOAPYRASES FROM SOLANUM-TUBEROSUM VAR ULTIMUS 
      Kettlun, Ana María; Urra, Raúl; Leyton, Mario; Valenzuela Pedevila, María Antonieta; Mancilla, Marta; Traverso Cori, A. (PERGAMON-ELSEVIER SCIENCE LTD, 1992-11)
      Two isoenzymes of ATP-diphosphohydrolase (apyrase) were extracted and purified from S. tuberosum var. Ultimus. Their hydrolytic activity ratios (ATPase/ADPase) were 1.0 (apyrase B) and ca 15.0 (apyrase A). They were ...
    • Optical activity of Co(III) ammine complexes and chiral ligands. Circular dichroism spectra of some CoN3O3 ... 
      Bunel Torrealba, Sergio; Ibarra, Carmen; Calvo Pérez, Víctor; Larrea, L. (Sociedad Chilena de Química, 1990)
      A partir de complejos amoniacales de Co(III) se sintetizaron compuestos que contienen los ligantes quirales L-aspartato y L-malato como segundo ligante. Los compuestos se identificaron por medio de análisis, mediciones de ...
    • ATP-diphosphohydrolase activity in rat renal microvillar membranes and vascular tissue 
      Sandoval, S.; García Nannig, Lorena; Mancilla, Marta; Kettlun, Ana María; Collados, L. E.; Chayet, L.; Alvarez, A.; Traverso Cori, A.; Valenzuela Pedevila, María Antonieta (PERGAMON-ELSEVIER SCIENCE LTD, 1996-05)
      Ecto-nucleotidases may have a role in the regulation of purinoceptor-mediated responses. ATP-diphosphohydrolase or apyrase has been described as an ecto-nucleotidase, which is characterized by a low specificity for its ...
    • Characterization of ATP-diphosphohydrolase from rat mammary gland 
      Alvarez, A.; Chayet, L.; Galleguillos, M.; García Nannig, Lorena; Kettlun, Ana María; Collados, L. E.; Traverso Cori, A.; Mancilla, M.; Valenzuela Pedevila, María Antonieta (PERGAMON-ELSEVIER SCIENCE LTD, 1996-01)
      ATP-diphosphohydrolase (or apyrase) hydrolyses nucleoside di- and triphosphates in the presence of millimolar concentration of divalent cations. It is insensitive towards sulfhydryl and aliphatic hydroxyl-selective reagents ...
    • HUMAN PLACENTAL ATP-DIPHOSPHOHYDROLASE - BIOCHEMICAL .CHARACTERIZATION, REGULATION AND FUNCTION 
      Kettlun, Ana María; Alvarez, A.; Quintar, R.; Valenzuela Pedevila, María Antonieta; Collados, L. E.; Aranda, E.; Banda, A.; Chayet, L.; Chiong Lay, Mario; Mancilla, Marta; Traverso Cori, A. (PERGAMON-ELSEVIER SCIENCE LTD, 1994-03)
      1. Kinetic and physico-chemical studies on human placental microsomal fraction confirmed that the ATPase and ADPase activities detected in this fraction correspond to the enzyme ATP-diphosphohydrolase or apyrase (EC 3.6.1.5). ...
    • ATPASE-ADPASE ACTIVITIES OF RAT PLACENTAL TISSUE 
      Pieber, M.; Valenzuela Pedevila, María Antonieta; Kettlun, Ana María; Mancilla, Marta; Aranda, E.; Collados, L. E.; Traverso Cori, A. (PERGAMON-ELSEVIER SCIENCE LTD, 1991)
      1. Calcium-stimulated ATPase-ADPase activities were studied in a microsomal fraction of rat placental tissue. 2. The kinetic characteristics correspond to those of ATP-diphosphohydrolase, also known as apyrase (E.C. ...
    • PHARMACOKINETICS OF NIFURTIMOX IN CHRONIC-RENAL-FAILURE 
      González Martin, G; Thambo Becker, Sergio; Paulos, Claudio; Vásquez, I.; Paredes, J. (SPRINGER VERLAG, 1992-06)
      The pharmacokinetics of nifurtimox. a drug used in the treatment of Trypanosoma cruzi infections, has been studied in seven patients with chronic renal failure undergoing haemodialysis, and in seven healthy subjects. Each ...
    • Drugs in prehistory: chemical analysis of ancient human hair 
      Báez Guerrero, Hernán; Camargo Grandón, Rodrigo; Benavente, M. A.; Kintz, P.; Castro Domínguez, Mario; Cirimele, V.; Thomas, C. (ELSEVIER SCI IRELAND LTD, 2000-02-28)
      Concern about drug abuse in modem populations has led to the development of specific methods for identification of cocaine, opiates and cannabis in human hair. Drug use in prehistory can provide indirect evidence of ...
    • Complexes of Co(III) with L-sorbose and phenanthroline 
      Blasko, Andrei; Bunton, Clifford A.; Moraga, Exequiel; Bunel Torrealba, Sergio; Ibarra, Carmen (ELSEVIER SCIENCE BV, 1995-12-20)
      L-Sorbose and two molecules of 1,10-phenanthroline form a complex with Co(III) which has the Lambda configuration about Co(III), based on CD and ORD spectra, The H-1 NMR signals of alpha-L-sorbopyranose and its mixed ...
    • COMPLEXES OF COBALT(III) WITH D-GLUCOSAMINE AND AMINES 
      Bunel Torrealba, Sergio; Ibarra, Carmen; Moraga, Exequiel; Calvo Pérez, Víctor; Blasko, Andrei; Bunton, Clifford A. (ELSEVIER SCIENCE BV, 1993-02-01)
      D-Glucosamine and ammonia, 1,2-ethylenediamine, or 1,10-phenanthroline form complexes with Co(III)*. The complexes are: [Co(NH3)3-H2O-D-glucosamine]3+, [Co(en)2.D-glucosamine]2+ and [Co(phen)2.D-glucosamine]3+. Formation ...
    • COMPLEXES OF COBALT(III) WITH D-FRUCTOSE AND PHENANTHROLINE 
      Moraga, Exequiel; Bunel Torrealba, Sergio; Ibarra, Carmen; Blasko, Andrei; Bunton, Clifford A. (ELSEVIER SCIENCE BV, 1995-03-01)
      D-Fructose and 1,10-phenanthroline form complexes with Co(III). Configurations about Co(III) are assigned from the CD and ORD spectra of the separated Lambda and Delta diastereomers, and Lambda strongly predominates in the ...
    • TRIAMMINE COBALT(III)-L-MALATE - MALATE ION AS A TRIDENTATE LIGAND 
      Bunel Torrealba, Sergio; Ibarra, Carmen; Calvo Pérez, Víctor; Blasko, Andrei; Bunton, Clifford A.; Keder, N. L. (PERGAMON-ELSEVIER SCIENCE LTD, 1991)
      The crystal structure of the title compound has been determined from single crystal X-ray diffraction data. There is little angle strain in the complex which has two carboxylate ions and one alkoxide ion bound to cobalt(III). ...
    • OPTICAL-ACTIVITY OF COMPOUNDS FORMED BY AMMINO COMPLEXES OF COBALT(III) AND CARBOHYDRATES .2. D-ARABINOSE COMPLEXES 
      Bunel Torrealba, Sergio; Ibarra, Carmen; Calvo Pérez, Víctor; Moraga, Exequiel (PERGAMON-ELSEVIER SCIENCE LTD, 1989)
    • Effect of protein-modifying reagents on ecto-apyrase from rat brain 
      Wink, M. R.; Buffon, A.; Bonan, C. D.; Valenzuela Pedevila, María Antonieta; Sarkis, J. J. K.; Battastini, A. M. O. (PERGAMON-ELSEVIER SCIENCE LTD, 2000-01)
      We have tested several chemical modifiers to investigate which amino acid residues, present in the primary structure of the ecto-apyrase, could be involved in catalysis. Synaptosomes from cerebral cortex of rats were ...