Koizumi K, Tanimoto T, Okada Y, Nakanishi N, Kato N, Takagi Y, Hashimoto H
Faculty of Pharmaceutical Sciences, Mukogawa Women's University, Nishinomiya, Japan.
Carbohydr Res. 1991 Aug 12;215(1):127-36. doi: 10.1016/0008-6215(91)84013-5.
It has been confirmed by methylation analyses and chemical syntheses that three isomers of branched cyclomaltoheptaose (beta CD) isolated from the mother liquors of a large-scale preparation of beta CD with Bacillus ohbensis cyclomaltodextrin glucanotransferase are 6(1),6(4)-di-O-(alpha-D-glucopyranosyl)-cyclomaltoheptaose (1), 6(1),6(3)-di-O-(alpha-D-glucopyranosyl)-cyclomaltoheptaose (2), and 6-O-(alpha-isomaltosyl)-cyclomaltoheptaose (4) instead of 6(1),6(2)-di-O-(alpha-D-glucopyranosyl)-cyclomaltoheptaose (3), which was erroneously characterized in an earlier paper. Compound 3 has been newly isolated from a glucosyl-beta CD mixture prepared by hydrolysis with glucoamylase of a maltosyl-beta CD mixture, synthesized from maltose and beta CD through the reverse action of pullulanase. Chromatographic behavior and spectral data (13C-n.m.r. and f.a.b.-m.s.) of these isomers of branched beta CD (1-4), as well as those of another isomer prepared by the reverse action of hydrolytic enzymes, 6-O-(alpha-maltosyl)-cyclomaltoheptaose (5), were compared.
通过甲基化分析和化学合成已证实，从用嗜碱芽孢杆菌环糊精葡聚糖转移酶大规模制备β-环糊精的母液中分离出的三种支链环麦芽七糖（β-环糊精）异构体分别是6(1),6(4)-二-O-(α-D-吡喃葡萄糖基)-环麦芽七糖（1）、6(1),6(3)-二-O-(α-D-吡喃葡萄糖基)-环麦芽七糖（2）和6-O-(α-异麦芽糖基)-环麦芽七糖（4），而非早期一篇论文中错误鉴定的6(1),6(2)-二-O-(α-D-吡喃葡萄糖基)-环麦芽七糖（3）。化合物3是从用麦芽糖基-β-环糊精混合物经糖化酶水解制备的葡萄糖基-β-环糊精混合物中新分离得到的，它是由麦芽糖和β-环糊精通过支链淀粉酶的逆反应合成的。比较了这些支链β-环糊精异构体（1-4）以及通过水解酶逆反应制备的另一种异构体6-O-(α-麦芽糖基)-环麦芽七糖（5）的色谱行为和光谱数据（13C-核磁共振和快原子轰击质谱）。
