Publications by authors named "Angelina Flores Parra"

In the title hydrated mol-ecular salt, 2CHN ·SO ·HO, the components are linked by numerous N-H⋯O and O-H⋯O hydrogen bonds.

View Article and Find Full Text PDF

The fluorescence properties of some imidazolium derivatives are relevant in photosensing and therefore, the structural analysis of them is a key point for its rational design, which would be useful to prepare new systems with novel applications. Herein we report a multidisciplinary study of the fluorescence and voltammetric properties of three imidazolium compounds {1,3-bis[(R,R)-1'-chloro-1'-phenylpropan-2'-yl]-imidazolium chloride (1), 1,3-bis[(Z)-1'-phenylprop-1'-en-2'-yl]imidazolium chloride (2) 1,3-bis[(R)-1'-chlorobutan-2'-yl]-imidazolium chloride (3)}. Electronic structure calculations and Bader analyses were used to correlate both fluorescence and the capability of the molecules to be reduced through a heterogeneous electron transfer process.

View Article and Find Full Text PDF

Fourteen new complexes were obtained from Ln(III)(NO)∙n-HO and the chromophores 2-(1H-benzo[d]imidazol-2-yl)-phenol (Bzp1) or 2-(5-methyl-1H-benzo[d]imidazol-2-yl)-phenol (Bzp2). The complete characterization allowed us to assign unequivocally the structures of all the complexes. The techniques used for this purpose were Ultraviolet-Visible (UV-Vis) and Fourier-Transform Infrared (FT-IR) spectroscopies, High-Resolution Mass Spectrometry (HRMS), Magnetic Susceptibility (MS), Elemental Analysis (EA) and Molar Conductivity (MC).

View Article and Find Full Text PDF

In the title polymeric complex salt, {[Ni(C8H4NO2)(C10H8N2)(H2O)3](C8H4NO2)} n , the Ni(II) cation is coordinated by a 4-cyano-benzoate anion, two 4,4'-bi-pyridine ligands and three water mol-ecules in a distorted N2O4 octa-hedral geometry. The 4,4'-bi-pyridine ligands bridge the Ni(II) cations to form polymeric chains of the title complex cations, propagating along the c-axis direction. The dihedral angle between the pyridine rings of the 4,4'-bi-pyridine ligand is 24.

View Article and Find Full Text PDF

Coordination compounds with cobalt(II), nickel(II), copper(II) and zinc(II) and the ligand 2,6-bis(2,6-diethylphenyliminomethyl)pyridine (L) were synthesized and fully characterized by IR and UV-Vis-NIR spectroscopy, elemental analysis, magnetic susceptibility and X-ray diffraction for two representative cases. These novel compounds were designed to study their activity as anti-proliferative drugs against different human cancer cell lines. The tridentate ligand forms heptacoordinated compounds from nitrate metallic salts, where the nitrate acts in a chelating form to complete the seven coordination positions.

View Article and Find Full Text PDF

In the title compound, [Co2(C7H5O2)4(C10H8N2)4]·6C6H5COOH, the centrosymmetric cobalt dimer co-crystallizes with six mol-ecules of benzoic acid. Each Co(II) atom is coordinated by four O atoms in a distorted square-planar arrangement while the N atoms are located in apical positions. The dihedral angles between the rings comprising each of the 4,4'-bipyridyl ligands are 25.

View Article and Find Full Text PDF

In the title salt, C23H21NOP(+)·Br(-), the dihedral angles between the phenyl rings are 70.41 (18), 73.6 (2) and 80.

View Article and Find Full Text PDF

In vitro antioxidant activity for 12 stannoxanes derived from Ph(3)SnCl (compounds 1-3), Ph(2)SnCl(2) (compounds 4-6), Bu(3)SnCl (compounds 7-9), and Bu(2)SnCl(2) (compounds 10-12), was assayed qualitatively by the chromatographic profile with 1,1-diphenyl-2-picrylhydrazil (DPPH) method and by two quantitative methods: the DPPH radical scavenging activity and Ferric-Reducing Antioxidant Power (FRAP) assays. The results were compared with those obtained with the starting materials 2-pyridine- carboxylic acid (I), 3-pyridinecarboxylic acid (II) and 4-pyridinecarboxylic acid (III), as well as with standard compounds, such as vitamin C and vitamin E, respectively. The in vitro antiradical activity with DPPH of diphenyltin derivative 5 showed a very similar behavior to vitamin C at a 20 microg/mL concentration, whereas according to the FRAP method, compound 8 was better.

View Article and Find Full Text PDF

Herein we report the synthesis, structural and spectroscopic characterization of coordination compounds with bis[2-(1H-benzimidazol-2-yl)phenyl]disulfide [bis-(2phSbz)] (1) and cobalt(II), zinc(II) and cadmium(II) halides (2-7). Their X-ray diffraction analyses showed that the metal ions present similar distorted tetrahedral structures, with the disulfide ligand coordinated through the imidazolic nitrogen atoms, forming a twisted eleven membered chelate ring. Structures of nickel(II) compounds 8 and 9, showed that the disulfide bond in the ligand was cleaved forming six membered chelates.

View Article and Find Full Text PDF

The reactions of AlMe(2)Y (Y = Me or Cl) with new ligands 2-(1,3,5-dithiazinan-5-yl)ethanol (1), 2-(1,3,5-dithiazinan-5-yl)-1-methylethanol (2), and 2-(1,3,5-dithiazinan-5-yl)-1-phenylethanol (3) are described. The ligands are coordinated to aluminum atoms by nitrogen and oxygen atoms, with a nitrogen based spiranic structure. Equimolar reactions gave dimeric structures bearing pentacoordinated aluminum atoms O-(AlMeY)-2-(1,3,5-dithiazinan-5-yl)ethanolates (4-7) as well as monometallic compounds with tetracoordinated aluminum atoms O-(AlMeY)-2-(1,3,5-dithiazinan-5-yl)ethanolates (8-9).

View Article and Find Full Text PDF