QSAR Studies of the Dioxins and Interaction of OCDD with Calix[4] Arene Using DFT

Quantum chemical calculations, based on Density Functional Theory (DFT) method, were performed on Calix[4]arene and Polychlorinated Dibenzo-p-dioxins (PCDDs) in gas and liquid phases for comparison purposes. The simulation results show the 1,2,3,4, 6,7,8,9-octachlorodibenzo-p-dioxin (OCDD) is quite a reactive dioxin. This paper attempts to examine the possibility of dioxin adsorption by Calix[n]arene from the environment. The interaction between Calix[4]arene and OCDD is investigated using the B3LYP method and LANL2DZ level of DFT in both gas and liquid phases. The results show that the OCDD acts as an electron acceptor and Calix[4]arene acts as an electron donor. A linear model of Quantitative Structure Activity Relationship (QSAR) has been approximated to calculate the binding affinity (BA) and induction potencies of aryl hydrocarbon hydroxylase (AHH) and 7-ethoxyresorufin O-deethylase (EROD). According to this model, the calculated BA of the dioxins were found to be close to their experimental values.