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Four cyclomaltooctaose derivatives 1a–d, which possess six mesitylsulfonyloxy groups on their C(6) atoms, were prepared. The assignment of the regiosiomers was performed by observing the long-range coupling through a glycoside linkage between H(1′) –C(4) and C(1′) –H(4) using a heteronuclear multiple-bond correlation (HMBC) method.

Three isomers of β-cyclodextrin derivatives 2a–c possessing two trimethylammonio groups on their C(6) atoms were prepared by reaction of the corresponding regioisomers of diamino compounds with methyl iodide. These derivatives recognize chiral guests through three-point interactions composed of both Coulomb interactions by the two cationic moieties and hydrophobic interaction by the molecularcavity.

A positively charged beta-cyclodextrin possessing a trimethylammonio group, 6-trimethylammonio-6-deoxy-beta-cyclodextrin chloride 1 was prepared by the reaction of an amino derivative 3 with methyl iodide under very mild conditions. The cyclodextrin derivative discriminated between enantiomers of acetylphenylalanine 2 on capillary zone electrophoresis (CZE) analysis, which was possibly due to an electrostatic interaction between the trimethylammonio group of 1 and the carboxylate group of 2, and also due to the inclusion of 2 in a hydrophobic molecular cavity of 1. Double data normalization based on relative electrophoretic velocity of peaks due to indirect response of 1 and also water in an injected sample may be effective for elimination of variation and fluctuation of physical parameters of medium, such as viscosity and ionic strength, in order to determine intrinsic association constants and velocity of the complexes.

Three isomers of cyclomaltoheptaose derivatives, 1a–c, which possess five mesitylenesulfonyloxy groups on their C-6 atoms, were prepared. Assignment of the regiosiomers was performed by their conversion into compounds containing five 3,6-anhydroglucose units followed by 1H NMR analyses. The structures of the pentakis(3,6-anhydro) derivatives were also confirmed by their derivation from the known bis(TBDMS) derivatives.

Novel cyclodextrin dimers (1, 2, 3 and 4) whose cyclodextrins were linked with sulfur-containing linkers, namely a thiodipropanamide, a dithiodipropanamide, a thiodiethanamide, or a dithiodiethanamide linker, were synthesized by a reaction of 6-amino-6-deoxycycIoheptaose 7 with the corresponding dicarboxylic acids. For their preparation, dicyclohexylcarbodiimide, l-(3-dimethylaminopropyl)-3-ethylcarbodiimideand(benzotriazol-l-yloxy) tripyrroIidinophosphonium hexafluorophosphate were examined as coupling reagents. 'H NMR studies of the dimers suggested an intramolecular inclusion of the linker moiety to the cyclodextrin cavity, which affected the complexation of guest molecules. Dimer 4 was converted to another type of dimer 5 by reductive cleavage of the disulfide bond to generate thiol group-containing mononieric species followed by a substitution reaction with 6-O-tosyl derivative 6.

Three isomers of cyclomaltoheptaose derivatives, la-c, which possess five mesitylenesulfonyloxy groups on their C-6 atoms, were prepared. Assignment of the regiosiomers was performed by their conversion into compounds containing five 3,6-anhydroglucose units followed by 'H NMR analyses. The structures of the pentakis(3,6-anhydro) derivatives were also confirmed by their derivation from the known bis(TBDMS) derivatives.

Three cyclomaltoheptaoses (1, 2 and 3) which possess a benzyloxycarbonylamino group, a tert-butoxycarbonylamino group or an azido group, and six tosyloxy groups, on their C-6 atoms have been prepared. These can be versatile intermediates for the synthesis of derivatives possessing an amino group as well as other functional groups. As an example of their derivatization, their conversion to compounds containing 3,6-anhydroglucoses, which possess cation-binding abilities, is also reported.

Novel cyclodextrin dimers (1, 2, 3 and 4) whose cyclodextrins were linked with sulfur-containing linkers, namely a thiodipropanamide, a dithiodipropanamide, a thiodiethanamide, or a dithiodiethanamide linker, were synthesized by a reaction of 6-amino-6-deoxycycloheptaose 7 with the corresponding dicarboxylic acids. For their preparation, dicyclohexylcarbodiimide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide and (benzotriazol-1-yloxy)tripyrrolidinophosphonium hexafluorophosphate were examined as coupling reagents. 1H NMR studies of the dimers suggested an intramolecular inclusion of the linker moiety to the cyclodextrin cavity, which affected the complexation of guest molecules. Dimer 4 was converted to another type of dimer 5 by reductive cleavage of the disulfide bond to generate thiol group-containing monomeric species followed by a substitution reaction with 6-O-tosyl derivative 6.

Three isomers of cyclomaltoheptaose derivatives, 1a–c, which possess five mesitylenesulfonyloxy groups on their C-6 atoms, were prepared. Assignment of the regiosiomers was performed by their conversion into compounds containing five 3,6-anhydroglucose units followed by 1H NMR analyses. The structures of the pentakis(3,6-anhydro) derivatives were also confirmed by their derivation from the known bis(TBDMS) derivatives.