Simple preparation of 3I-O-substituted β-cyclodextrin derivatives using cinnamyl bromide

[GRAPHIC] A new method for preparation of 3(I)-O-substituted beta-cyclodextrin derivatives was developed. Cinnamyl bromide reacts with beta-cyclodextrin to form predominantly the 31-0-cinnamyl derivative (30% isolated yield, > 90% regioselectivity). After protection of the remaining cyclodextrin hydroxyls by acetylation, the cinnamyl group can be easily transformed to many other groups (exemplified by transformation to 3(I)-O-carboxymethyl derivative). Substitution pattern in singly modified CDs was unambiguously determined by a combination of 2D NMR techniques.