Center for Self-assembly and Complexity (CSC), Institute for Basic Science (IBS), Pohang, 790-784 (Republic of Korea); Department of Chemistry, and Division of Advanced Materials Science, Pohang University of Science and Technology, Pohang, 790-784 (Republic of Korea) http://csc.ibs.re.kr/
Angew Chem Int Ed Engl. 2014 Jan 20;53(4):1003-7. doi: 10.1002/anie.201308879. Epub 2013 Dec 5.
Cucurbit[7]uril (CB[7]), an uncharged and water-soluble macrocyclic host, binds protonated amino saccharides (D-glucosamine, D-galactosamine, D-mannosamine and 6-amino-6-deoxy-D-glucose) with excellent affinity (Ka =10(3) to 10(4) M(-1) ). The host-guest complexation was confirmed by NMR spectroscopy, isothermal titration calorimetry (ITC), and MALDI-TOF mass spectral analyses. NMR analyses revealed that the amino saccharides, except D-mannosamine, are bound as α-anomers within the CB[7] cavity. ITC analyses reveal that CB[7] has excellent affinity for binding amino saccharides in water. The maximum affinity was observed for D-galactosamine hydrochloride (Ka =1.6×10(4) M(-1) ). Such a strong affinity for any saccharide in water using a synthetic receptor is unprecedented, as is the supramolecular stabilization of an α-anomer by the host.
葫芦脲（CB[7]）是一种不带电荷且水溶性的大环主体，对质子化的氨基糖（D-葡萄糖胺、D-半乳糖胺、D-甘露糖胺和 6-氨基-6-去氧-D-葡萄糖）具有极好的亲和力（Ka=10(3) 至 10(4) M(-1)）。通过 NMR 光谱、等温热滴定（ITC）和 MALDI-TOF 质谱分析证实了主客体络合。NMR 分析表明，氨基糖除了 D-甘露糖胺之外，均以α-异构体的形式结合在 CB[7]空腔内。ITC 分析表明，CB[7]在水中对结合氨基糖具有极好的亲和力。与盐酸 D-半乳糖胺（Ka=1.6×10(4) M(-1)）的亲和力最大。使用合成受体在水中对任何糖都具有如此强的亲和力是前所未有的，而主体对α-异构体的超分子稳定作用也是前所未有的。
