Synthesis ofβ-cyclodextrin-based dendrimer as a novel encapsulation agent

Abstract

The aim was the fabrication of glycodendrimer encapsulation agents with high proportions of cyclodextrins (CDs) to maintain the biocompatibility properties, as well as to notably improve their ability to load various suitably sized drugs. The novel glycodendrimers contained β-CD in both core and branches, namely β-cyclodextrin-based dendrimer (CD-dendrimer) prepared through a straightforward procedure using SN2 displacement to attach multivalent β-CDs together. The desired CD-dendrimer was synthesized in three steps: (i) reaction of β-CD with p-toluenesulfonyl chloride and/or iodine to afford C-6 mono- and/or per-β-CD derivative; (ii) reaction of the β-CD precursors with ethylenediamine to give C-6 mono- and/or per-amino-β-CD derivative; and (iii) SN2 displacement of β-CD electrophilic derivative with β-CD nucleophilic derivative in dimethylsulfoxide to provide the CD-dendrimer. Then, the encapsulation behaviour of the CD-dendrimer was examined using naproxen and naltrexone as the guest molecules. The structure of the designed CD-dendrimer allowed two types of possible sites for encapsulation of the guest: in cavities of the dendritic structure and in hydrophobic cavities of CDs. © 2013 Society of Chemical Industry