Theoretical investigation of the complexation, structural, and electronic properties of complexes between oseltamivir drug and cucurbit[n = 6–9]urils

The structural geometries of cucurbit[n]uril CB[n] with n = 6–9 and their complexes oseltamivir (OST) drug were obtained using the density functional theory computations. stationary points most stable confirmed vibrational frequency calculation. complexation energies electronic properties CB[n]/OST investigated. calculated results indicate that intermolecular interactions in all studied occur via a large number dipole–dipole interactions, especially hydrogen bonds between oxygen atoms amine drug. negative both gas water phases host–guest are exothermic process more than its bare CB[n]. In addition, CB[7]/OST complex is complexes. calculation for each CBs complexations spontaneous process. NBO analysis shows transferring partial charge from CB[n]s to which correspond MEP contours. HOMO LUMO orbitals localized on After complexation, also display energy gaps significantly changed. All point out can act as host appropriately guest, even aqueous solution.