Publicaciones 2011-2020

@article{RN321,
title = {Protonation Sites, Tandem Mass Spectrometry and Computational Calculations of O-Carbonyl Carbazolequinone Derivatives},
author = { M. Martinez-Cifuentes and G. Clavijo-Allancan and P. Zuniga-Hormazabal and B. Aranda and A. Barriga and B. Weiss-Lopez and R. Araya-Maturana},
url = {/brokenurl#<Go to ISI>://WOS:000381500900086},
doi = {UNSP 1071, 10.3390/ijms17071071},
issn = {1422-0067},
year = {2016},
date = {2016-01-01},
journal = {International Journal of Molecular Sciences},
volume = {17},
number = {7},
abstract = {A series of a new type of tetracyclic carbazolequinones incorporating a carbonyl group at the ortho position relative to the quinone moiety was synthesized and analyzed by tandem electrospray ionization mass spectrometry (ESI/MS-MS), using Collision-Induced Dissociation (CID) to dissociate the protonated species. Theoretical parameters such as molecular electrostatic potential (MEP), local Fukui functions and local Parr function for electrophilic attack as well as proton affinity (PA) and gas phase basicity (GB), were used to explain the preferred protonation sites. Transition states of some main fragmentation routes were obtained and the energies calculated at density functional theory (DFT) B3LYP level were compared with the obtained by ab initio quadratic configuration interaction with single and double excitation (QCISD). The results are in accordance with the observed distribution of ions. The nature of the substituents in the aromatic ring has a notable impact on the fragmentation routes of the molecules.},
keywords = {antitumor assignment, basicities, c-13 carbazole, chemistry complete derivatives, dft, gas-phase hydroquinone ionization, mass molecules, nmr-spectra, qcisd, quinones, respiration, spectrometry, tumor-cell},
pubstate = {published},
tppubtype = {article}
}

@article{RN322,
title = {Small Structural Changes on a Hydroquinone Scaffold Determine the Complex I Inhibition or Uncoupling of Tumoral Oxidative Phosphorylation},
author = { F.A. Urra and M. Cordova-Delgado and M. Lapier and A. Orellana-Manzano and L. Acevedo-Arevalo and H. Pessoa-Mahana and J.M. Gonz\'{a}lez-Vivanco and M. Martinez-Cifuentes and O. Ramirez-Rodriguez and J.P. Millas-Vargas and B. Weiss-Lopez and M. Pavani and J. Ferreira and R. Araya-Maturana},
url = {/brokenurl#<Go to ISI>://WOS:000378100100006},
doi = {10.1016/j.taap.2015.12.005},
issn = {0041-008x},
year = {2016},
date = {2016-01-01},
journal = {Toxicology and Applied Pharmacology},
volume = {291},
pages = {46-57},
publisher = {2015 Elsevier Inc},
abstract = {Mitochondria participate in several distinctiveness of cancer cell, being a promising target for the design of anti-cancer compounds. Previously, we described that ortho-carbonyl hydroquinone scaffold 14 inhibits the complex I-dependent respiration with selective anti-proliferative effect on mouse mammary adenocarcinoma TA3/Ha cancer cells; however, the structural requirements of this hydroquinone scaffold to affect the oxidative phosphorylation (OXPHOS) of cancer cells have not been studied in detail. Here, we characterize the mitochondrial metabolism of TA3/Ha cancer cells, which exhibit a high oxidative metabolism, and evaluate the effect of small structural changes of the hydroquinone scaffold 14 on the respiration of this cell line. Our results indicate that these structural changes modify the effect on OXPHOS, obtaining compounds with three alternative actions: inhibitors of complex I-dependent respiration, uncoupler of OXPHOS and compounds with both actions. To confirm this, the effect of a bicyclic hydroquinone (9) was evaluated in isolated mitochondria. Hydroquinone 9 increased mitochondrial respiration in state 4o without effects on the ADP-stimulated respiration (state 3(ADP)), decreasing the complexes I and II-dependent respiratory control ratio. The effect on mitochondrial respiration was reversed by 6-ketocholestanol addition, indicating that this hydroquinone is a protonophoric uncoupling agent. In intact TA3/Ha cells, hydroquinone 9 caused mitochondrial depolarization, decreasing intracellular ATP and NAD(P)H levels and GSH/GSSG ratio, and slightly increasing the ROS levels. Moreover, it exhibited selective NAD(P)H availability-dependent anti-proliferative effect on cancer cells. Therefore, our results indicate that the ortho-carbonyl hydroquinone scaffold offers the possibility to design compounds with specific actions on OXPHOS of cancer cells.},
keywords = {anti-cancer apoptosis, calu-6 cancer-cells, cell cells, complex derivatives, dysfunction, energy-metabolism, hydroquinones, i, liver-mitochondria, mitochondrial oxidative phosphorylation, respiration, ta3, uncouplers},
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}
}

@article{RN34e,
title = {Nmr Assignment in Regioisomeric Hydroquinones},
author = { J.A. Dobado and J.C. Gomez-Tamayo and F.G. Calvo-Flores and H. Martinez-Garcia and W. Cardona and B. Weiss-Lopez and O. Ramirez-Rodriguez and H. Pessoa-Mahana and R. Araya-Maturana},
url = {/brokenurl#<Go to ISI>://WOS:000291114500009},
doi = {10.1002/mrc.2745},
issn = {0749-1581},
year = {2011},
date = {2011-01-01},
journal = {Magnetic Resonance in Chemistry},
volume = {49},
number = {6},
pages = {358-365},
publisher = {2011 John Wiley & Sons, Ltd.},
abstract = {A set of regioisomeric pairs of tricyclic hydroquinones, analogues of antitumor 9,10-dihydroxy-4,4-dimethyl-5,8dihydroanthracen- 1(4H)-one (1) and other derivatives, were synthesized and their regiochemistry and NMR spectra assigned by using 1H-detected one-bond(C-H) HMQC and long-range C-HHMBC, in good agreement with theoretical O3LYP/Alhrichs-pVTZ calculations. The 5-hydroxymethyl derivatives (11, 15, 19) showed a 3 integral H,H coupling constant of methylene protons evidencing the presence of a seven-membered intramolecular hydrogen bonded ring, not observed for the 8-hydroxymethyl isomers.},
keywords = {basis-sets, c-13 calculations, chemical-shifts, coupling-constants, derivatives, dft, diels-alder giao, h, h-1 hmbc, hmqc, hydroquinone, nmr, o3lyp, organic-molecules, reaction, respiration, sensitivity, spin theoretical tumor-cell},
pubstate = {published},
tppubtype = {article}
}