title: Theoretical and Experimental Study of Inclusion Complexes of β-Cyclodextrins with Chalcone and 2',4'-Dihydroxychalcone.
abstract: The inclusion complexes formed by chalcone and 2',4'-dihydroxychalcone with β-cyclodextrin have been studied combining experimental (phase solubility diagrams, Fourier transform infrared spectroscopy) and molecular modeling (molecular dynamics, quantum mechanics/molecular mechanics calculations) techniques. The formation constants of the complexes were determined at different temperatures, and the thermodynamic parameters of the process were obtained. The inclusion of chalcone in β-cyclodextrin is an exothermic process, while the inclusion of 2',4'-dihydroxychalcone is endothermic. Free energy profiles, derived from umbrella sampling using molecular dynamics simulations, were constructed to analyze the binding affinity and the complexation reaction at a molecular level. Hybrid QM/MM calculations were also employed to obtain a better description of the energetic and structural aspects of the complexes. The intermolecular interactions that stabilize both inclusion complexes were characterized by means of quantum atoms in molecules theory and reduce density gradient method. The calculated interactions were experimentally observed using FTIR.
authors.affiliation: Universidad Nacional de San Luis , Facultad de Química, Bioquímica y Farmacia, IMIBIO-CONICET, Chacabuco 917, 5700, San Luis, Argentina.
authors.forename: Matias I
authors.initials: MI
authors.lastname: Sancho
authors.affiliation: Universidad Nacional de San Luis , Facultad de Química, Bioquímica y Farmacia, IMIBIO-CONICET, Chacabuco 917, 5700, San Luis, Argentina.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Andujar
authors.affiliation: Instituto de Matemática Aplicada San Luis (IMASL), CONICET, Facultad de Ciencias Físico Matemáticas y Naturales, Universidad Nacional de San Luis , Av. Ejército de los Andes 950, 5700, San Luis, Argentina.
authors.forename: Rodolfo D
authors.initials: RD
authors.lastname: Porasso
authors.affiliation: Universidad Nacional de San Luis , Facultad de Química, Bioquímica y Farmacia, IMIBIO-CONICET, Chacabuco 917, 5700, San Luis, Argentina.
authors.forename: Ricardo D
authors.initials: RD
authors.lastname: Enriz
mesh_terms: D002599:Chalcone / Q000737:chemistry*; D047188:Chalcones / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D011789:Quantum Theory; D013816:Thermodynamics; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D047188:Chalcones; D047392:beta-Cyclodextrins; C059354:2',4'-dihydroxychalcone; D002599:Chalcone