Study on Molecular Recognition of Pinocembrin with Methylated-β-Cyclodextrin

Abstract The inclusion behavior, inclusion capacity and inclusion mode of pinocembrin (PIN) with dimethyl- β -cyclodextrin (DM- β -CD) and trimethyl- β -cyclodextrin (TM- β -CD) were characterized by X-ray diffraction (XRD), thermal analysis, scanning electron microscopy (SEM), UV-visible spectral titration and molecular docking. The results showed that the packing ratio of PIN/DM- β -CD complex and PIN/TM- β -CD complex was 1:1. The water solubility of PIN increased by 817 times and 575 times in the inclusion complex with DM- β -CD and TM- β -CD, respectively. Molecular docking showed the PIN entered from the large end of the DM- β -CD molecule and penetrated through the cavity. The A and B rings of the PIN were respectively located at the big and small ends of the CD molecule. For the TM- β -CD, only A and C rings of the PIN entered the cavity of CD.