Study on the inclusion behavior and solid inclusion complex of 5-amino-6-methyl-2-benzimidazolone with cyclodextrins

The inclusion behaviors of three native or modified CDs including β-CD, 2-hydroxypropyl-β-CD (2-Hp-β-CD) and 2,6-dimethyl-β-CD (Me-β-CD) toward 5-amino-6-methyl-2-benzimidazolone (AMBI) were comparatively investigated by NMR and fluorescence titration in combination with IR spectra, X-ray diffractometry and scanning electron microphotographs. The experimental results jointly demonstrated that the phenyl ring of AMBI entered into the cavity of the CDs and located close to the narrow rims accompanied by the formation of the 1:1 inclusion complex with large stability constant in aqueous solution. The introduction of the hydroxypropyl unit to the host improved the solubility, ultimately effecting an obvious promoting in the fluorescence intensity and the stability constant

The inclusion behaviors of three native or modified CDs including β-CD, 2-hydroxypropyl-β-CD (2-Hp-β-CD) and 2,6-dimethyl-β-CD (Me-β-CD) toward 5-amino-6-methyl-2-benzimidazolone (AMBI) were comparatively investigated by NMR and fluorescence titration in combination with IR spectra, X-ray diffractometry and scanning electron microphotographs. The experimental results jointly demonstrated that the phenyl ring of AMBI entered into the cavity of the CDs and located close to the narrow rims accompanied by the formation of the 1:1 inclusion complex with large stability constant in aqueous solution. The introduction of the hydroxypropyl unit to the host improved the solubility, ultimately effecting an obvious promoting in the fluorescence intensity and the stability constant.Figure optionsDownload as PowerPoint slide