Synthesis of beta-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 beta-CD in both core and branches, namely beta-cyclodextrin-based dendrimer (CD-dendrimer) prepared through a straightforward procedure using S(N)2 displacement to attach multivalent beta-CDs together. The desired CD-dendrimer was synthesized in three steps: (i) reaction of beta-CD with p-toluenesulfonyl chloride and/or iodine to afford C-6 mono- and/or per-beta-CD derivative; (ii) reaction of the beta-CD precursors with ethylenediamine to give C-6 mono- and/or per-amino-beta-CD derivative; and (iii) S(N)2 displacement of beta-CD electrophilic derivative with beta-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. (C) 2013 Society of Chemical Industry