Addition of p-toluenesulfonic anhydride (Ts2O) to beta-cyclodextrin (CD) in water, followed by treatment with 10% aqueous NaOH solution for 10 min and removal of excess Ts2O by filtration, gave mono-6-deoxy-6-(O-p-toluenesulfonyl)-CD (1) in 61% yield. (C) 1998 Elsevier Science Ltd. All rights reserved.