Abstract
Cyclomaltodecaose (ε-cyclodextrin, ε-CD), cyclomaltoundecaose (ζ-CD) and cyclomaltotridecaose (θ-CD) are a series of cyclomalto-oligosaccharides composed of ten, eleven and thirteen α-(1→4)-linked D-glucopyranose units, respectively. ε-CD, ζ-CD and θ-CD were purified from the commercially available CD powder mainly using the combined treatment of HPLC and column chromatographies. The molecular weights of ε-CD, ζ-CD and θ-CD were determined by FAB-MS, and their cyclic structures were identified by 1H-NMR and 13C-NMR. Furthermore, the 13C-NMR chemical shift of large-ring cyclodextrins composed of several α-(1→4)-linked D-glucopyranose units, in which numbers 9, 10, 11, 12, and 13 are named δ-, ε-, ζ-, η-, θ-CD, were elucidated and compared with those of conventional α-, β-, and γ-CD.