Abstract

A new and convenient method is presented for the preparation of mono-2 or mono-3-O-benzoyl-ß-cyclodextrin by direct benzoylation of ß-cyclodextrin on the secondary hydroxyl face using N-benzoylimidazole in carbonate buffer solution. These processes involved the solvent-dependent equilibriums of isomerization to improve the yields. Among the common solvents
(N,N-dimethylform-amide, dimethyl sulfoxide and H₂O), dimethyl sulfoxide is the most advantageous for preparing mono-2-O-benzoyl-ß-cyclodextrin and H₂O is the most advantageous for preparing mono-3-O-benzoyl-ß-cyclodextrin.

Keywords

Cyclodextrin, Benzoylation, Isomerization, Equilibrium