Mono-, Di-, or Triazidated Cyclodextrin-Based Polyrotaxanes for Facile and Efficient Functionalization via Click Chemistry

As a feasible way for controlling the density of ligands in polyrotaxanes, azidated polyrotaxanes comprising PEG (MW = 3 000 and 20 000 g . mol(-1)) and mono-, di-, or triazidated alpha-cyclodextrins are prepared in a water/DMSO solution in a one-pot synthesis. The azidated polyrotaxanes are then allowed to conjugate with propargyl-modified mannose as a ligand via click chemistry. As proven by FTIR spectroscopy and H-1 NMR-spectroscopy, mannose molecules are efficiently introduced into all of the azidemoieties of the polyrotaxanes. The results verify the achievement of ligand-density-controlled polyrotaxanes. The functionalized polyrotaxanes can be utilized for a variety of biological applications.