1H NMR spectra of branched-chain cyclomaltohexaoses (α-cyclodextrins) Original Research Article

The 1H NMR spectra of seven branched α-cyclodextrins (α-CDs) were observed and analyzed in detail. They were compared with spectra of α-CD and amylose. Although these branched α-CDs consist only of α-d-glucose with the same α-(1 → 4) O-glucosyl binding, aside from one exception, differences in chemical shifts of corresponding signals were significantly large. Especially, differences in the chemical shift in anomeric protons were considerably large. Subtle differences in glucosyl binding directly influences chemical shifts of these protons because anomeric protons are located adjacent to the glucosyl binding sites.