Molecular docking study on b-cyclodextrin Interactions of metobromuron and [3-(p-bromophenyl)-1-methoxy-1- methylurea]

Abstract

The inclusion process involving b-cyclodextrin (b-cyclodextrin-CD) and phenylurea herbicide metobromuron (MB) has been investigated by using the MM?, PM3, B3LYP, HF, ONIOM2 and NBO methods. The binding and complexation energies for both orientations considered in this research are reported. The geometry of the most stable complex shows that the aromatic ring is deeply selfincluded inside the hydrophobic cavity of b-CD also an intermolecular hydrogen bond is established between hostand guest molecules. This suggests that hydrophobic effect and hydrogen bond play an important role in the complexation process. The statistical thermodynamic calculations by PM3 demonstrate that 1:1 MB/b-CD complex is favored by a negative enthalpy change. Moreover, NBO calculations proved also that are a very useful means to quantify the interaction energies of the hydrogen bonds.