Investigation of the inclusion interaction of p-sulfonatocalix[6]arene with trimebutine maleate

The inclusion complexation behavior of p-sulfonatocalix[6]arene (SCX6) with trimebutine maleate (TMB) was investigated by fluorescence spectroscopy, NMR spectroscopy, infrared spectroscopy (IR), differential scanning calorimetry (DSC) as well as scanning electron microphotographs (SEM). The results indicated that TMB was able to form an inclusion complex with SCX6. The formation constant (K) of the complex was calculated and the inclusion complexes had a 1/1 stoichiometry at different pH values (pH = 3.00, 6.00, 8.00). The NMR studies showed that the 2-dimethylamino-2-phenylbutyl side of TMB could be encapsulated in the cavity of SCX6.