The inclusion interaction between an anti inflamatory with β-cyclodextrin

The inclusion interactions between β-cyclodextrin (β-CD) and diclofenac (DCF) were simulated using the semiempirical PM3 and ONIOM (B3LYP/3-21g: PM3) methods. The modeling results showed that the most stable geometry of DCF into β-CD complex is B orientation inclusion, in which the phenyl acetate moiety is included inside the hydrophobic cavity of β-CD. The results showed that the binding energy (BE) and total stabilization energy (EONIMO) of B orientation are lower than A orientation, indicating that the B orientation is more stable than the A orientation, Furthermore, it can be deduced from the results obtained by NBO analysis that the main driving forces of DCF/β-CD are weak hydrogen bonding interaction.