Publicaciones 2011-2020

@article{RN372,
title = {Experimental and Theoretical Reduction Potentials of Some Biologically Active Ortho-Carbonyl Para-Quinones},
author = { M. Martinez-Cifuentes and R. Salazar and O. Ramirez-Rodriguez and B. Weiss-Lopez and R. Araya-Maturana},
url = {/brokenurl#<Go to ISI>://WOS:000404517800075},
doi = {10.3390/molecules22040577},
issn = {1420-3049},
year = {2017},
date = {2017-01-01},
journal = {Molecules},
volume = {22},
number = {4},
abstract = {The rational design of quinones with specific redox properties is an issue of great interest because of their applications in pharmaceutical and material sciences. In this work, the electrochemical behavior of a series of four p-quinones was studied experimentally and theoretically. The first and second one-electron reduction potentials of the quinones were determined using cyclic voltammetry and correlated with those calculated by density functional theory (DFT) using three different functionals, BHandHLYP, M06-2x and PBE0. The differences among the experimental reduction potentials were explained in terms of structural effects on the stabilities of the formed species. DFT calculations accurately reproduced the first one-electron experimental reduction potentials with R-2 higher than 0.94. The BHandHLYP functional presented the best fit to the experimental values (R-2 = 0.957), followed by M06-2x (R-2 = 0.947) and PBE0 (R-2 = 0.942).},
keywords = {aprotic-solvents, aqueous-solution, batteries botrytis-cinerea, computational cyclic density density-functional electrochemistry, electron-transfer, functional ion models, p-benzoquinone, potential, properties, quinones, redox semiquinone, solvation theory, voltammetry},
pubstate = {published},
tppubtype = {article}
}

@article{RN215,
title = {Intramolecular Hydrogen Bond in Biologically Active O-Carbonyl Hydroquinones},
author = { M. Martinez-Cifuentes and B. Weiss-Lopez and L.S. Santos and R. Araya-Maturana},
url = {/brokenurl#<Go to ISI>://WOS:000340036200041},
doi = {10.3390/molecules19079354},
issn = {1420-3049},
year = {2014},
date = {2014-01-01},
journal = {Molecules},
volume = {19},
number = {7},
pages = {9354-9368},
abstract = {Intramolecular hydrogen bonds (IHBs) play a central role in the molecular structure, chemical reactivity and interactions of biologically active molecules. Here, we study the IHBs of seven related o-carbonyl hydroquinones and one structurally-related aromatic lactone, some of which have shown anticancer and antioxidant activity. Experimental NMR data were correlated with theoretical calculations at the DFT and ab initio levels. Natural bond orbital (NBO) and molecular electrostatic potential (MEP) calculations were used to study the electronic characteristics of these IHB. As expected, our results show that NBO calculations are better than MEP to describe the strength of the IHBs. NBO energies (Delta E-ij((2))) show that the main contributions to energy stabilization correspond to LP ->sigma* interactions for IHBs, (O1O2)-O-center dot center dot center dot-H-2 and the delocalization LP ->pi* for O-2-C-2 = C-alpha(beta). For the (O1O2)-O-center dot center dot center dot-H-2 interaction, the values of Delta E-ij((2)) can be attributed to the difference in the overlap ability between orbitals i and j (F-ij), instead of the energy difference between them. The large energy for the LP O-2 ->pi* C-2 = C-alpha(beta) interaction in the compounds 9-Hydroxy-5-oxo-4,8, 8-trimethyl-1, 9(8H)-anthracenecarbolactone (VIII) and 9,10-dihydroxy-4,4-dimethylanthracen-1(4H)-one (VII) (55.49 and 60.70 kcal/mol, respectively) when compared with the remaining molecules (all less than 50 kcal/mol), suggests that the IHBs in VIII and VII are strongly resonance assisted.},
keywords = {ab-initio, bond bond, chemistry, derivatives, dft, diels-alder electrostatic hydrogen hydroquinone, inhibitors, molecular molecules, natural orbital, potential, quinones, radicals reaction, resonance, respiration, tumor-cell},
pubstate = {published},
tppubtype = {article}
}