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区域选择性 (13) - 葡萄糖的thexyldimethylsilylation - 链接类型是否重要

Andreas Koschella¹, Thomas Heinze¹, Etienne Severac²

¹Friedrich Schiller University Jena, Institute for Organic Chemistry and Macromolecular Chemistry, Center of Excellence for Polysaccharide Research, Humboldtstraße 10, D-07743 Jena, Germany.

Carbohydrate polymers

|August 22, 2024

概括

这项研究表明,thexyldimethylchlorosilane (TDMS-Cl) 在α-(13) 结合的葡萄糖中选择性地化原基,提供比纤维素或粉更受控制的修饰.

科学领域:

碳水化合物化学碳水化合物化学
聚合物科学聚合物科学
有机合成有机合成

背景情况:

多糖的修饰对于开发新材料至关重要.
基组的选择性功能化仍然是一个挑战.
氧化二甲基化 (TDMS-Cl) 提供了区域选择性衍生物化的潜力.

研究的目的:

调查TDMS-Cl化在α-和β-(13) 结合多糖体上的区域选择性.
为了比较TDMS-Cl与纤维素和粉等其他多糖的反应性和选择性.
开发一种合成这些多糖的乙甲基衍生物的方法.

主要方法:

在N,N-二甲基乙胺 (DMA) 中溶解α-和β-(13) 结合的多糖.
在pyridine的存在下与TDMS-Cl反应的多糖.
进行甲基化,脱化和乙化.
使用核磁共振 (NMR) 光谱分析产品.

主要成果:

在TDMS群体中实现了0.7到1.0之间的替代度 (DS_Si).
与β-(13) 相关的库德兰的反应性 (DS_Si 0.7) 比与α-(13) 相关的葡萄糖 (DS_Si大约) 低. 1). 1). 一个 1). 一个 1).
核磁共振揭示了初级OH组 (位置6) 的高度选择性化,优于纤维素和粉.
转换 (14) 结合的多糖化合物产生了6-mono-O-和2,6-di-O-化单元,区域选择性6-mono-O-化需要危险的液体氨.

结论:

在α-(13) 结合的葡萄糖中,TDMS-Cl对主要基组具有很高的区域选择性.
这种选择性明显高于纤维素和粉所观察到的.
开发的合成序列可以获得具有受控替代模式的乙甲基衍生物.

关键词:

核磁共振光谱法 (NMR) 是一种光谱法.它是一种多糖化合物.区域活动性区域活动性选择性沉是一种选择性的沉.

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