A series of ruthenium azopyridine complexes have recently been investigated due to their potential cytotoxic activities against renal cancer (A498), lung cancer (H226), ovarian cancer (IGROV), breast cancer (MCF-7) and colon cancer (WIDR). Thus, in order to predict the cytotoxic potentials of these compounds, quantitative structure-activity relationship studies were carried out using the methods of quantum chemistry. Five Quantitative Structure Activity Relationship (QSAR) models were obtained from the determined quantum descriptors and the different activities. The models present the following Moreover, the charge of the ligand is the priority descriptor for the prediction of the cytotoxicity of the compounds studied. Furthermore, QSAR models developed are statistically significant and predictive, and could be used for the design and synthesis of new anti-cancer molecules.

Ruthenium complexes present two states of oxidation that are Ru(II) and Ru(III). Both are assumed to present cytotoxic activity at ground state. On the purpose of highlighting their differences, DFT, TD-DFT and NBO have been performed at both Wb97xd/Lanl2dz and B3lyp/Lanl2dz levels. NBO program shows that both groups of ruthenium complexes present almost the same charge of Ru atom. Moreover, they display nearly the same structure of valence orbitals of the ruthenium. However, when it comes to compare their frontier orbitals HOMO and LUMO, we notice that the chloride atom has a great influence on their energy. The lack of Chloride atoms reduces the energy of frontier orbitals regardless of the functional. And the more the number of chloride atoms, the higher the energy. Also, RuCl 3

The heterogenized δ-RuCl 2 (Nazpy) 2 deposited on carbon toray (CT) was studied for the first time as electrochemical catalyst. Before, it was characterized by visible-ultraviolet spectra and theoretically by TDDFT method at B3LYP/Lanl2DZ level. It displayed an MLCT t 2g e g → π* transition where t 2g e g due to the structure of Nazpy that considerably reduces energy between d AOs of Ru represents the HOMO of the complex and π* is identified as the LUMO. Electrochemistry study shows two redox ranges in both negative and positive sides of the potential. The positive side that corresponds to the couple Ru IV /Ru III of catalyst appears to be active for oxidation of D-glucose in carbonate buffer with a high turnover. Therefore, Keto-2-gluconic and gluconic acids were the two main products obtained with respectively 80% and 17.6% of selectivity. Moreover, a small amount of tartaric and glycol acids coming from the c-c bond cleavage due to non-protection of the anomeric carbon of D-glucose were also observed.

We focused on a series of coumarin derivatives in this work. The method of Density Functional Theory (DFT) of quantum chemistry has been used at B3LYP / 6-31G (d, p) level in order to identify molecular descriptors which are useful for this study. The analysis of the statistical indicators allowed to obtain a QSAR model based on quantum descriptors and anti-cancer activity against breast cancer (MCF-7) that were accredited for good statistical performance. For the model, the statistical indicators were: correlation coefficient R2 = 0.904, standard deviation S = 0.102, Fischer test coefficient F = 18.779 and correlation coefficient of cross validation

<p>In this work, the density functional theory (DFT) method at the B3LYP/6-31 + G (d, p) level has used to determine the optimization of five rhodanine derivatives. The stability of the derivatives (7a-7e) of 5-arylidene rhodanine, the hyperconjugative interactions, the delocalization of the atomic charges was analyzed with the analysis of the Natural Bond Orbital (NBO). The electronic structures were discussed and the relocation of electronic density was determined. Molecular Electrostatic Potential (MEP), local density functional descriptors, border molecular orbitals and absorption spectrum were studied. Through the local Fukui reactivity indices, the carbon of the carbonyl group (C = O) is the preferential site of the nucleophilic attack and the sulfur atom linked to the trigonal carbon (C = S) is the preferential site of electrophile attack. Analysis of the global descriptors revealed that compound 7c is the most reactive with an energy difference between the frontier orbitals of ΔEgap = 3.305 eV. Furthermore, this compound 7c is the less stable, the softest and has the greatest electronic exchange capacity of all studied compounds. The intramolecular electronic transitions which stabilize these compounds are LP → π * for 7a and 7d and σ → σ * for 7b, 7c and 7e. The rhodanine derivatives are more reactive and more soluble in polar solvents.</p>