Theoretical and Experimental Study of Inclusion Complexes of β‐Cyclodextrins with Chalcone and 2′,4′-Dihydroxychalcone

MATIAS SANCHO; ANDUJAR SEBASTIAN; RODOLFO PORASSO; ENRIZ RICARDO

JOURNAL OF PHYSICAL CHEMISTRY B - (Print)

AMER CHEMICAL SOC

Lugar: Washington; Año: 2016

1520-6106

The inclusion complexes formed by chalcone and2′,4′-dihydroxychalcone with β-cyclodextrin have been studiedcombining experimental (phase solubility diagrams, Fourier transforminfrared spectroscopy) and molecular modeling (molecular dynamics,quantum mechanics/molecular mechanics calculations) techniques.The formation constants of the complexes were determined atdifferent temperatures, and the thermodynamic parameters of theprocess were obtained. The inclusion of chalcone in β-cyclodextrin isan exothermic process, while the inclusion of 2′,4′-dihydroxychalconeis endothermic. Free energy profiles, derived from umbrella samplingusing molecular dynamics simulations, were constructed to analyzethe binding affinity and the complexation reaction at a molecularlevel. Hybrid QM/MM calculations were also employed to obtain abetter description of the energetic and structural aspects of thecomplexes. The intermolecular interactions that stabilize both inclusion complexes were characterized by means of quantumatoms in molecules theory and reduce density gradient method. The calculated interactions were experimentally observed usingFTIR.