chelation. Di- or trisaccharides containing a 6-O-glycosylated mannopyranoside or galactopyranoside at their reducing ends had bending abilities similar to that of the Hin monosaccharide, probably because there were neither attractive nor repulsive interactions between the reducing and nonreducing ends. However, when Hin was attached at O2 of methyl mannopyranoside (Man alphaMe), the bending ability was
合成了将2,4-二
氨基-β-D-
吡喃
吡喃糖苷作为铰链单元(Hin)的铰链二糖和三糖。通过羰基化或螯合将Hin的二
氨基桥接成
金属离子会导致从(4)C1到(1)C4的构象变化,进而导致
寡糖弯曲。在这项研究中,根据对羰基化和螯合的反应性,比较了铰链
寡糖的弯曲能力。在其还原末端含有6-O-糖基化的甘露
吡喃糖苷或半
乳糖吡喃糖苷的二糖或三糖具有类似于Hin
单糖的弯曲能力,这可能是因为在还原末端和非还原末端之间既没有吸引性相互作用也不具有排斥作用。但是,当Hin附着在甲基甘露
吡喃糖苷(Man alphaMe)的O2上时,弯曲能力取决于非还原糖和反应条件。通常,二糖-Hin beta(1,2)Man alphaMe-在所有测试的反应条件下都难以弯曲,并且在存在Zn(II)的情况下弯曲的种群仅为4%。另一方面,三糖-Man alpha(1,3)Hin beta(1,2,Man alphaMe)-加入Zn(I