Showing papers by "Enrique J. Baran published in 1999"
34 citations
Journal Article•
TL;DR: The infrared spectra of the bis-chelated Cu(I1) complexes of the amino acids glycine, alanine, leucine, isoleuceine, valine and phenylalanine were recorded and analyzed in relation to its structural peculiarities as discussed by the authors.
Abstract: SUMMARY. The infrared spectra of the bis-chelated Cu(I1) complexes of the amino acids glycine, alanine, leucine, isoleuceine, valine and phenylalanine, which posses different kind of pharmacologic activity, were recorded and analyzed in relation to its structural peculiarities. Some comparisons between the recorded spectra are also presented and the characteristics of the carboxylate motions as well as those of the metal-to-ligand vibrations are discussed in detail. RESUMEN. "Espectros de Infrarrojo de los Complejos de Cobre(I1) de Aminoacidos con Residuos Hidrofobicos". Los espectros de infrarrojo de los complejos de Cu(II), bisquelados con los aminoacidos glicina, alanina, leucina, isoleucina, valina y fenilalanina, conocidos por presentar diferentes tipos de actividad farmacologica, fueron registrados y analizados en base a sus peculiaridades estructurales. Asimismo, se presentan algunas comparaciones entre los espectros obtenidos y las caracteristicas de las vibraciones asociadas a los grupos carboxilato y a las uniones metal-ligando se discuten en detalle.
12 citations
TL;DR: The synthesis and crystal structure of a new Mg(II) complex of stoichiometry, where isoor is the monoanion of 5-carboxyuracil (isoorotic acid), and dissolution studies support the usefulness of the compound for magnesium supplementation.
10 citations
TL;DR: In this article, a Re(III) complex with thiourea derivatives was synthesized by reduction of perrhenate with tin(II) chloride in 2N hydrochloric acid in the presence of excess alkylthiourerea.
9 citations
TL;DR: In this paper, a new ReV oxo complex with tetramethylthiourea, [ReO(Me4tu)4](PF6)3, has been synthesized by reduction of perrhenate with tin(II) chloride in strongly acidic solution.
Abstract: A new ReV oxo complex with tetramethylthiourea, [ReO(Me4tu)4](PF6)3, has been synthesized by reduction of perrhenate with tin(II) chloride in strongly acidic solution in the presence of excess tetramethylthiourea. The complex has been characterized by elemental analysis and electronic and FTIR spectroscopy. The molecular structure of the compound was determined by X-ray diffraction methods. The coordination polyhedron is a regular square pyramid with the substituted thiourea sulfur atoms in the equatorial positions [d(Re–S) = 2.339(3) A] and the oxo ligand located in the summit [d(Re–O) = 1.63(2) A]. Computational methods were employed to analyze the geometric and electronic structures of tetramethylthiourea and thiourea. Quantum mechanical studies suggest steric hindrance as the reason for the stabilization of the ReO3+ center instead of the ReIII one.
8 citations
TL;DR: In this article, the infrared and Raman spectra of Nd2CuGe2O 8 were recorded and assigned on the basis of its structural characteristics and compared with other germanates of the same type containing different lanthanide cations (Sm-Tm) and yttrium.
Abstract: The infrared and Raman spectra of Nd2CuGe2O 8 were recorded and assigned on the basis of its structural characteristics. The study was complemented with an analysis of the infrared spectra of other germanates of the same type containing different lanthanide cations (Sm–Tm) and yttrium, and by comparison with related materials. Copyright © 1999 John Wiley & Sons, Ltd.
8 citations
TL;DR: In this article, the infrared and Raman spectra of Pb4(PO4)2SO4 were recorded and interpreted with the aid of a site symmetry analysis and some comparisons with related species are made.
Abstract: The infrared and Raman spectra of Pb4(PO4)2SO4 were recorded and interpreted with the aid of a site symmetry analysis. Some comparisons with related species are made. Copyright © 1999 John Wiley & Sons, Ltd.
6 citations
TL;DR: The thermal behavior of a series of oxovanadium(IV) complexes of halogenated derivatives of 8-hydroxyquinoline was investigated by means of TG and DTA measurements in oxygen atmosphere.
Abstract: The thermal behaviour of a series of oxovanadium(IV) complexes of halogenated derivatives of 8-hydroxyquinoline was investigated by means of TG and DTA measurements in oxygen atmosphere. V2O5 was the final pyrolysis residue in all cases.
6 citations
TL;DR: In this paper, the synthesis and X-ray crystal and molecular structures of a new Li(I) complex of stoichiometry [Li(isoor)H 2 O] 2, where isoor is the monoanion of 5-carboxyuracil (isoorotic acid), are reported.
6 citations
5 citations
TL;DR: In this article, the electrochemical behavior of VOQ2OH or [VOQ2-OVOQ2] (Q = 8-hydroxyquinohnate anion) has been investigated by cyclic voltammetry in acetonitnie solutions.
Abstract: The electrochemical behavior of VOQ2OH or [VOQ2-OVOQ2] (Q = 8-hydroxyquinohnate anion) has been investigated by cyclic voltammetry in acetonitnie solutions. Although both species exist simultaneously at every condition analyzed, they can be clearly differentiated by this method. The effect of trace amounts of water on the electrochemical behavior is also discussed.
TL;DR: The Fourier transform-infrared and Raman spectra of the two mercury orthorasenates were recorded and assigned on the basis of their structural characteristics and are discussed in comparison with related compounds as mentioned in this paper.
Abstract: The Fourier transform-infrared and Raman spectra of the two mercury orthorasenates were recorded and assigned on the basis of their structural characteristics and are discussed in comparison with related compounds Copyright © 1999 John Wiley & Sons, Ltd
TL;DR: In this article, the FT-IR spectrum of Auranofin, the drug (2,3,4,6-tetra-O-acetyl-1-thio-β- d -glucopyranosato-S) (triethylphosphine gold(I)), was recorded and assigned on the basis of its known crystal structure and by comparisons with the characteristic vibrations of its constituent structural units.
TL;DR: In this paper, the electrochemical behavior of ethylic esters derived from the oxo-vanadium(V) complex Q2VO(OH) was investigated by cyclic voltamperometry in organic solvents.
Abstract: The electrochemical behavior of ethylic esters of the type Q2VO(OEt), derived from the oxo-vanadium(V) complex Q2VO(OH) (Q = 8-hydroxyquinoline, 5-chloro and 5, 7-dichloro-8-hy-droxyquinoline or 2-methyl-8-hydroxyquinoline), was investigated by cyclic voltamperometry in organic solvents. The detailed analysis of the results confirmed the generation of different complex species in solution. The presence of water in the solvents modifies the electrochemical behavior, as a consequence of the formation of a mixed valence dimer of the type [Q2VO-O-OVQ2]−. The somewhat different behavior of the 2-methyl-8-hydroxyquinoline derivative could also be explained. The analysis of the electronic spectra of the investigated solutions, after and during the electrochemical measurements, gave additional support to some of the proposed reactions, steps and mechanisms.
01 Jan 1999
TL;DR: In this article, the synthesis of three Mg(I1) complexes potentially useful for magnesium supplementation in human and veterinary medicine was presented, which were characterized by IR and Raman spectroscopy and their thermal behaviour was investigated by means of thermogravimetric measurements and differential tliermal analysis, working in oxygen atmosphere.
Abstract: We present the synthesis of three Mg(I1) complexes potentially useful for magnesium supplementation in human and veterinary medicine: magnesium chloro-aspartate, Mg(C4H604N)C1.3Hz0; magnesium citrate, ~g(H20)6][MgC6H507(H20)]25Hz0, and magnesium orotate, [Mg(C5H304N2)2].8H20. These compounds were characterized by IR and Raman spectroscopy and their thermal behaviour was investigated by means of thermogravimetric measurements and differential tliermal analysis, working in oxygen atmosphere. RESUMEN. "Comportamiento Espectroscopico y Termico de Compuestos Complejos Utiles para la Suplementacioii de Magiiesio". Se presenta la sintesis de tres complejos de Mg(I1) potencialniente utiles para la suplementacioii de este elemento en medicina Iiumaiia y veterinaria: cloro-aspartato de magnesio, Mg(C4H6O4N)Cl.3H2O; citrato de magiiesio, [Mg(H20)6][MgC6H507(H20)]2.5Hfl; y orotato de magnesio, [Mg(C5H304N2)2].8H20. Estos compuestos se caracterizaron a traves de sus espectros de IR y Raman y su comportamiento termico fue investigado por terinograviiiietria y analisis termico diferencial, trabajando en corriente de oxigeno.
01 Jan 1999
TL;DR: The results support the potential usefulness of this double carbonate as a useful compound for Zn(II) supplementation.
01 Jan 1999
TL;DR: The thermal behavior of Auranofin, one of the best established gold containing drugs, has been investigated by thermogravimetric and differential thermal analysis under an oxygen flow.
Abstract: The thermal behaviour of Auranofin, one of the best established gold containing drugs, has been investigated by thermogravimetric and differential thermal analysis under an oxygen flow. A detailed decomposition mechanism could be postulated. Elemental gold is the final pyrolysis product. RESUMEN. "Comportamiento termico de la Auranofina". El comportamiento termico de la Auranofina, uno de los farmacos a base de oro mejor conocidos, fue investigado por analisis termogravimetrico y termico-diferencial, en corriente de oxigeno. Fue posible postular un mecanismo detallado para la descomposicion. El producto final de la pirolisis es oro elemental.
TL;DR: Mean amplitudes of vibration of the recently reported pentagonal bipyramidal SbF72 and BiF72 dianions were calculated from vibrational spectroscopic data, in the temperature range between 0 and 1000 K as mentioned in this paper.
Abstract: Mean amplitudes of vibration of the recently reported pentagonal bipyramidal SbF72- and BiF72- dianions were calculated from vibrational spectroscopic data, in the temperature range between 0 and 1000 K. The results are briefly discussed and some comparisons with related species are made.
TL;DR: In this article, the infrared and Raman spectra of a platinum complex of the antiinflammatory drug piroxicam and dimethylsulfoxide of composition [PtCl2Pir(DMSO)] were recorded and briefly discussed on the basis of its structural characteristics.
Abstract: The infrared and Raman spectra of a platinum complex of the antiinflammatory drug piroxicam (Pir) and dimethylsulfoxide (DMSO) of composition [PtCl2Pir(DMSO)] were recorded and briefly discussed on the basis of its structural characteristics. The metal-to-ligand vibrations are analyzed in detail.