Now showing items 1-20 of 20

    • Caglioti, V.; Furlani, C.; Dessy, G.; Ibarra, Carmen (Societá Chimica Italiana, 1962)
      Sono stati preparati diversi tipi di complessi del rame con diammine alifatiche a lunga catena di atomi di C, correpondenti alle formule: CuCl2.1/2 am (giallo), CuCl2.am (verde) e CuCl2.am(azzurro o viola), dove am = ...
    • 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.
    • 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 ...
    • 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 ...
    • 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 ...
    • Blasko, Andrei; Bunton, Clifford A.; Bunel Torrealba, Sergio; Ibarra, Carmen; Moraga, Exequiel (Elsevier Science Publishers B. V., 1997)
      Acid dissociation constants of α- and β-D-glucos-, mannos-, and galactos-ammonium ions have been determined from 1H NMR chemical shifts of the individual anomers in D2O. Values of pKa(D) for the α- and β-ammonium ions ...
    • Parada Aliste, José; Bunel Torrealba, Sergio; Ibarra, Carmen; Larrazábal Rojas, Guillermo; Moraga, Exequiel; Gillitt, N. D.; Bunton, Clifford A. (ELSEVIER SCI LTD, THE BOULEVARD, 2001-07-12)
      Sucrose forms a dicationic complex with cobalt(III)bis(phenanthroline) which can be isolated as the sparingly water-soluble triiodide salt or the water-soluble chloride. The circular dichroism (CD) spectrum demonstrates ...
    • 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 ...
    • Bunel Torrealba, Sergio; Ibarra, Carmen; Rodríguez, M.; Urbina, A.; Bunton, Clifford A. (Pergamon Press Ltd., 1981)
      Mixed 1:1:1 complexes of proline or aspartic acid with Cu(II) and 9:10-phenanthroline (phen) or 2,2'bipyridine (bipy) show induced Cotton effects in the aromatic region. The effect is ascribed to interactionsbetween the ...
    • Parada Aliste, José; Larrazábal Rojas, Guillermo; Mendoza, Jorge; Cañón, Walter; Ibarra, Carmen (SOCIEDAD CHILENA DE QUIMICA, 2006-06)
      Mixed complexes of animosugars and 1,10-phenanthroline (phen) with cobalt(III), with the composition Co(III)(phen)(2)sugar, disproportionate in aqueous solution in approximately one month, giving non ionic tris-aminosugar ...
    • 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 ...
    • 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 ...
    • Ibarra, Carmen; Soto, R.; Adán, L.; Decinti Weiss, Emilio; Bunel Torrealba, Sergio (Elsevier Sequoia, 1972)
      Complexes of Cu(II) and Ni(II) with L-aminoacids have been prepared and their UV spectra and optical activity studied. The results are interpreted in terms of the conformation of the chelated rings. A molecular orbital ...
    • Bunel Torrealba, Sergio; Ibarra, Carmen; Calvo Pérez, Víctor; Moraga, Exequiel (PERGAMON-ELSEVIER SCIENCE LTD, 1989)
    • Bunel Torrealba, Sergio; Ibarra, Carmen; Rodríguez, M.; Urbina, A.; Bunton, Clifford A. (Pergamon Press, 1981)
      Complexes of Cu(II) with L-aminoacids have positive charge transfer bands in their CD spectra at ca.230 nm and negative at ca. 270 nm. Examination of complexes with L-1,2-diamino propane shows that the positive band is ...
    • Larrazábal Rojas, Guillermo; Bunel Torrealba, Sergio; Ibarra, Carmen; Parada Aliste, José (SOCIEDAD CHILENA DE QUIMICA, 2002-03)
      Reaction between cis-[Co(NH3)(H2O)(2)](3-) and ammonia in aqueous solution, in the presence of a carbohydrate, leads to the formation of the tetranuclear complex of cobalt (III): [Co-4(NH3)(12)(OH)(6)](6+) partially resolved. ...
    • Bunel Torrealba, Sergio; Ibarra, Carmen; Moraga, Exequiel; Blasko, Andrei; Bunton, Clifford A. (Elsevier Science Publishers B.V., 1993)
      The 1H NMR signals of the hydrochlorides of 2-amino-2-deoxy-α and β -D-Glucose (α-and β-D-glucosamine) have been assigned and chemical shifts and coupling constants determined from their phase-sensitive COSY spectra in ...
    • Parada Aliste, José; Ibarra, Carmen; Gillitt, N. D.; Bunton, Clifford A. (PERGAMON-ELSEVIER SCIENCE LTD, 2005-06-28)
      The title compound (sucrose Co(phen)(2)) is a dication with the Delta-configuration at Co(III) and ligation through O-2(g) and OH-1(f). Earlier geometrical optimization with semi-empirical PM3(tm) parameters had fitted ...
    • Bunel Torrealba, Sergio; Ibarra, Carmen; Rodríguez, M.; Urbina, A.; Bunton, Clifford A. (Pergamon Press Ltd., 1981)
    • 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). ...