Synthesis and conformation of dihistamine derivatives of cyclomaltoheptaose (β-cyclodextrin)

The three isomeric dihistamine derivatives of β-cyclodextrin (cyclomaltoheptaose) have been prepared and investigated by 1H- and 13C-n.m.r. spectroscopy. For each isomer, neither of the imidazole rings is included in the cavity, but a reciprocal influence of the histamine chains is observed, suggesting that they have an organised structure.