Solid state inclusion compound of S-ibuprofen in β-cyclodextrin:: structure and characterisation

A crystalline inclusion complex was isolated from the reaction of beta-cyclodextrin (betaCD) with aqueous S-(+)-ibuprofen (S-Ibu). The existence of a true inclusion complex in the solid state was confirmed by a combination of powder X-ray diffraction (XRD), single crystal X-ray diffraction, thermogravimetric analysis (TGA), FTIR and C-13 CP MAS NMR spectroscopies. The inclusion compound crystallises in the non-centrosymmetric monoclinic space group C2 with a 2: 1 host: guest stoichiometry. The crystal structure consists of a head-to-head dimer of betaCD molecules stacked along the crystallographic c axis, thus forming a slightly tilted channel-type structure.