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通过保护组的反应性调整进行立体选择性1.1'-糖化

Daniele Zucchetta¹, Karin Hofbauer¹, Alla Zamyatina¹

¹Department of Chemistry, University of Natural Resources and Life Sciences, Muthgasse 18, Vienna, A-1190 Austria. alla.zamyatina@boku.ac.at.

Organic & biomolecular chemistry

|January 17, 2025

概括

合成像二甲糖胺这样的非还原性分糖是具有挑战性的. 这项研究开发了一种立体选择性化学糖化法,利用保护组来控制β,β-和β,α连接糖的立体化学.

科学领域:

碳水化合物化学碳水化合物化学
有机合成有机合成
立体选择性合成立体选择性合成

背景情况:

对于非还原性二糖化物合成的1.1'-糖化,需要控制两个异构中心的立体化学.
虽然α,α-disaccharides已经得到了很好的研究,但与β,β-和β,α结合的非降解糖的合成仍未得到充分探索.
自然存在的分糖和仿真物通常具有不对称的功能组,因此需要可靠的方法来对正交保护的1.1'-结合糖进行检测.

研究的目的:

开发立体选择方法来合成β,β-和β,α结合的非降解糖.
创建一个完全正交保护的β,β-和β,α结合型二甲糖胺的库.
为了研究保护组对甘氨基化立体选择性的影响.

主要方法:

利用保护群对甘氨酸捐赠体和乳糖受体的电子和扭曲效应.
调整直角保护组以调节乳醇受体反应率和异构形状.
确定甘氨基醇供体-乳糖醇受体对的结构-活性关系.

主要成果:

实现了高度立体选择性的β,β-和β,α-1,1'-糖化.
成功合成了一个完全正交保护的β,β-和β,α-结合的双葡萄糖胺的库.
证明保护乳糖核友性的群体驱动调制是立体选择性甘油酸结合形成的关键.

结论:

保护群体策略对于控制1.1'-糖基化中的立体化学是至关重要的.
开发的方法可以获得有价值的正交保护的β,β-和β,α结合的二甲糖胺.
这项工作促进了生物分子应用复杂碳水化合物的合成.

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