Kazutaka Koga

Synthesis of fullerene–cyclodextrin conjugates

[60] Fullerene derivatives bearing α-, β- and γ-cyclodextrin units as hydrophobic binding sites have been synthesized by the reaction of C60 and peracetylated cyclodextrin 6-azides in chlorobenzene. The C60–β-cyclodextrin conjugate demonstrated efficient quenching effect on the bound photo-luminescent guest rhodamine B.

The first topologically controlled synthesis of doubly bridged β-cyclodextrin dimers

Reaction 6(A),6(B)-di(O-tosyl)-beta-cyclodextrin with Na(2)S in DMF gave the cis-dimer of beta-cyclodextrin in 21% isolated yield while the trans-dimer was not detected.

Regioselective transannular disulfonylation on the 6A, 6C positions of α-cyclodextrin

Abstract α-Cyclodextrin reacts with dibenzofuran-2,8-disulfonyl chloride in pyridine leading to the selective formation of 6A,6C-transannularly disulfonylated α-CD in 18% yield.

Molecular sugar bowl: γ-cyclodextrin with a disaccharide floor

Abstract A series of molecular sugar bowls composed of a γ-cyclodextrin wall and a trehalose floor have been synthesized by reacting 6A,6X-deoxy-6A,6X-dimercapto-γ-cyclodextrin and 6,6′-deoxy-6,6′-diiodotrehalose.

Synthesis and unique NMR behaviour of a novel capped α-cyclodextrin

1,3-Bis(benzimidazol-2-yl)benzene-capped α-cyclodextrin 1 is synthesized by reaction of 6A,6C-bix-O-mesitylenesulfonyl substituted α-cyclodextrin with o-phenylenediamine and subsequent cyclocondensation with isophthaldehyde 4, and its highly resolved NMR spectra are described.

Fluorophore-capped cyclodextrins as efficient chemical-to-light energy converters.

Bisbenzimidazole-capped cyclodextrins, capable of forming supramolecules, harvest chemical energy from the oxidation reaction of a bis(aryl)oxalate and emit light two orders of magnitude more efficiently than fluorescein does.

Synthesis and Properties of Phenylenebisbenzimidazole Capped β-Cyclodextrins

Abstract Novel capped β-cyclodextrins were synthesized by reaction of 6 A ,6 C (or 6 A ,6 D )-bis- O -tosyl substituted β-cyclodextrins with o -phenylenediamine and subsequent cyclocondensation with iso -phthalaldehyde 4 . Their highly resolved NMR spectra and binding property are also described.

Regiospecific one-point cleavage of capped β-cyclodextrin by taka-amylase a

Abstract A cyclic compound 2 composed of glucoses and biphenyl was prepared in 21% yield through regiospecific cleavage of the glucose-wall of 6 A ,6 D -di- O -(p,p′-biphenyldisulfonyl)-β-cyclodextrin 1 by Taka-amylase A.

Selective modification of β-cyclodextrin: an unexpected tandem reaction enables the cross-linking of C2A and C2B via a sulfur atom

2(A),3(A)-Alloepithio-2(B)-sulfonyl-beta-cyclodextrin undergoes a tandem reaction to generate an unprecedented C2(A)-S-C2(B)-bridged glucosyl-3(A),6(A)-anhydroglucoside segment.