Publications by authors named "Mircea Oltean"

Genistein is one of the most studied phytocompound in the class of isoflavones, presenting a notable estrogenic activity and in vitro and/or in vivo benefits in different types of cancer such as those of the bladder, kidney, lung, pancreatic, skin and endometrial cancer. A big inconvenience for drug development is low water solubility, which can be solved by using hydrophilic cyclodextrins. The aim of this study is to theoretically analyze, based on the interaction energy, the possibility of a complex formation between genistein (Gen) and three different ramified cyclodextrins (CD), using a 1:1 molar ratio Gen:CD.

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Potential energy curves along the inter-planar coordinates have been calculated for the dimers of two perylene derivatives (PTCDI and PTCDA) by using MP2 and dispersion corrected DFT (DFT-D) methods with B3LYP, B97 and PBE0 density functionals. The performance of dispersion-correcting potentials (DCPs) for describing intermolecular van der Waals interactions was also tested in conjunction with PBE0 and B971 functionals. Analytical potential energy curves were derived at different levels of theory by fitting the calculated data to modified Morse, Murrell-Sorbie, Buckingham and Lennard-Jones potentials.

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A simple, fast and accurate method of chiral recognition and quantification of propranolol enantiomers by surface enhanced Raman scattering (SERS) and multivariate regression analysis through supramolecular interaction with β-cyclodextrin is reported. Computational chemistry served as a tool of elucidating the underlying mechanism of molecular interactions responsible for chiral discrimination. The influence of several factors (nature and concentration of chiral auxiliary, selector-selectand ratio, pH, interaction time, etc.

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Absorption spectra of PTCDI (3,4,9,10-perylene-tetracarboxylic-diimide) have been investigated in chloroform, N,N'-dimethylformamide (DMF) and dimethylsulfoxide (DMSO). While no signature of assembled PTCDI molecules is observed in chloroform solution, distinct bands assigned to their aggregation have been identified in DMF and DMSO solutions. PTCDI monomers show very similar absorption patterns in chloroform and DMSO solutions.

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Rotational motions of ferrocene-based carousels have been achieved by electron transfer centered on π-dimerizable 4,4'-bipyridinium substituents introduced on both cyclopentadienyl rings through covalent linkers of different size, geometry, and flexibility. Detailed spectroscopic, electrochemical, and theoretical analyses demonstrate that rigid and fully conjugated linkers allow the quantitative formation of intramolecular π-dimers resulting from optimized orbital overlaps within the HOMO of the electrochemically generated bis-radical species. The tetra-cationic "charge-repelled" conformers, the self-assembled π-dimers, and their electron triggered interconversions have been investigated by UV-vis, NMR, and ESR spectroscopy, electrochemistry, X-ray diffraction analysis, and theoretical calculations.

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