Browsing by Author "Gutiérrez Oliva, Soledad"
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- ItemBridging the gap between the topological and orbital description of hydrogen bonding: The case of the formic acid dimer and its sulfur derivatives(2006) Gutiérrez Oliva, Soledad; Joubert, L.; Adamo, C.; Bulat Jara, Felipe Alfonso; Zagal, J.H.; Toro Labbé, Alejandro
- ItemComplexation of AAPH (2,2′-azobis(2-methylpropionamidine) dihydrochloride) with cucurbit[7]uril enhances the yield of AAPH-derived radicals(2023) Forero Girón, Angie; Fuentealba Patiño, Denis Alberto; Mariño Ocampo, Nory Johana; Gutiérrez Oliva, Soledad; Herrera Pisani, Bárbara Andrea; Toro Labbé, Alejandro; Fuentes Lemus, Eduardo; Davies, Michael J.; Aliaga Miranda, Margarita Elly; López Alarcón, Camilo IgnacioAAPH (2,2′-azobis(2-methylpropionamidine) dihydrochloride), a water-soluble azo compound is widely employed to produce peroxyl radicals for chemical and biological studies. This compound is shown herein to form a stable inclusion complex with cucurbit[7]uril (CB7), a well-established supramolecular host. Competitive binding assays using berberine dye, isothermal titration calorimetry (ITC), and nuclear magnetic resonance (1H-NMR) experiments, provided evidence for the inclusion of AAPH inside the CB7 cavity with a binding constant of 2.5 ± 0.8 x 105 L mol-1 (determined by ITC). Computational analysis at B3LYP-D3BJ/6-311G(d,p) of the complex (AAPH@CB7) showed interactions of the positively-charged amino groups of AAPH with carbonyl functions at the CB7 entrances. Photolysis of AAPH@CB7 by illumination at 365 nm, gave a higher yield of carbon-centered radicals when compared to the absence of CB7, as evidenced by electron paramagnetic resonance spin trapping using α-phenyl-N-t-butylnitrone. Enhanced radical formation was corroborated by increased consumption of pyrogallol red, free Trp and Trp-containing peptides when these were exposed to AAPH@CB7 in the presence of light. The increased yield of radicals generated by AAPH@CB7 is believed to arise from a pull effect of CB7 portals on initial AAPH-derived carbon-centered radicals generated by photolysis. It is proposed that these radicals are exposed and released to the bulk solution and react with O2 to give peroxyl radicals. These results suggest that the AAPH@CB7 complex can be used to generate high yields of peroxyl radicals for their use in studying these species in material, environmental and biomedical sciences amongst others.
- ItemComputational study of the supramolecular complexation of azocompounds with cucurbit[7]uril: effects on the production and release of free radicals(Springer Science and Business Media Deutschland GmbH, 2024) Forero Girón, Angie; Gutiérrez Oliva, Soledad; López Alarcón, Camilo Ignacio; Herrera Pisani, Bárbara Andrea; Aliaga Miranda, Margarita EllyContext: An inclusion complex between 2,2′-azobis(2-methylpropionamidine) dihydrochloride (AAPH), a widely employed azocompound, and cucurbit[7]util (CB[7]), has shown an increased yield of radicals derived from the homolytic cleavage of the azo bond. Aimed to get insights about the formation of complexes and their effect on the yield of radicals production, complexes of CB[7] with seven azocompounds were studied by computational methods. Molecular electrostatic surfaces and structural analysis showed that the inclusion of symmetrical azocompounds inside of CB[7] depends mainly on the charge density and position of the functional groups at the main chain of the azoderivative. Analysis of non-covalent interactions and thermodynamic outcomes revealed that positively charged azocompounds with amidinium or imidazolium groups presented strong favorable interactions (multiple hydrogen bonds) with the oxygens of CB[7] portals. Additionally, carbon-centered radicals generated from the complexes (azocompounds@CB[7]) were corroborated using the electron localization function (ELF). Results evidenced that the strength of the interactions and the level of inclusion (partial or complete) between the azocompound and CB[7] determined the final orientation of the radicals (located out- or inside of the CB[7] cavity). Obtained results could be employed to design new supramolecular systems based on the properties of azocomplound@CB[7] complexes for new scientific or industrial applications. Methods: First-principles calculations at B3LYP-D3BJ/6-311g(d,p) level theory in the gas phase and in solvent (PCM, water) were performed in Gaussian 16 software package. The dispersion energy correction was included through the Grimme’s dispersion with Becke-Johnson damping D3(BJ). Thermodynamical data and the minimum character of all structures were obtained from vibrational frequency calculations. NBO, Multiwfn, Chemcraft, and NCIPLOT software were used to perform population analysis, analyze outcomes, visualize data, and display non-covalent interactions respectively.
- ItemElectropolymerization of 3 ',4 '-disubstituted 2,2 ':5 ',2 ''-terthiophene derivatives. A theoretical and photovoltaic characterization(2011) Vélez Cifuentes, Jorge; Gutiérrez Oliva, Soledad; Díaz Alzamora, Fernando Raúl; Valle de la Cortina, María Angélica del; Toro Labbé, Alejandro; Bernede, Jean C.; East, Gaston A.
- ItemETS-NOCV Decomposition of the Reaction Force: The HCN/CNH Isomerization Reaction Assisted by Water(2017) Díaz Acosta, Silvia Andrea; Brela, Mateusz Z.; Gutiérrez Oliva, Soledad; Toro Labbé, Alejandro; Michalak, Artur
- ItemIdentification of pseudodiatomic behavior in polyatomic bond dissociation: Reaction force analysis(2010) Murray, Jane S.; Toro Labbé, Alejandro; Gutiérrez Oliva, Soledad; Politzer, Peter
- ItemInsights into the Mechanism of Ground and Excited State Double Proton Transfer Reaction in Formic Acid Dimer(2017) Giri, S.; Parida, R.; Jana, M.; Gutiérrez Oliva, Soledad; Toro Labbé, Alejandro
- ItemMolecular hydrogen formation in the interstellar medium : the role of polycyclic aromatic hydrocarbons analysed by the reaction force and activation strain model(2018) Barrales Martínez, César Camilo; Cortés Arriagada, Diego; Gutiérrez Oliva, Soledad
- ItemStudy of antiradical mechanisms with dihydroxybenzenes using reaction force and reaction electronic flux(2017) Ortega Moo, Cristin; Durán, Rocio; Herrera Pisani, Bárbara Andrea; Gutiérrez Oliva, Soledad; Toro Labbé, Alejandro; Vargas, Rubicelia
- ItemSymmetry-adapted reaction electronic flux in cycloaddition reactions(2016) Villegas, Nery Andrés; Vogt Geisse, Stefan Alexander; Gutiérrez Oliva, Soledad; Toro Labbé, Alejandro
- ItemThe Influence of the Metal Cations and Microhydration on the Reaction Trajectory of the N3 ↔ O2 Thymine Proton Transfer: Quantum Mechanical Study(2017) Šebesta, Filip; Brela, Mateusz Z.; Diaz, Silvia; Miranda, Sebastián; Murray, Jane S.; Gutiérrez Oliva, Soledad; Toro Labbé, Alejandro; Michalak, Artur; Burda, Jaroslav V.
- ItemThe reaction electronic flux in chemical reactions(2011) Cerón, María Luisa; Echegaray Zipper, Eleonora Ana Luisa; Gutiérrez Oliva, Soledad; Herrera Pisani, Bárbara Andrea; Toro Labbé, Alejandro
- ItemThe reaction electronic flux: A new descriptor of the electronic activity taking place during a chemical reaction. Application to the characterization of the mechanism of the Schiff's base formation in the Maillard reaction(2010) Flores Morales, Patricio; Gutiérrez Oliva, Soledad; Silva Stevens, Eduardo Andrés; Toro Labbé, Alejandro
- ItemThe reaction force : three key points along an intrinsic reaction coordinate(2005) Politzer, Peter; Toro Labbé, Alejandro; Gutiérrez Oliva, Soledad; Herrera Pisani, Bárbara Andrea; Jaque Olmedo, Pablo César; Concha, Mónica C.; Murray, Jane S.