糖辅助的糖与复杂的寡糖结合:范围和局限性
Clay S Bennett1, Stephen M Dean, Richard J Payne
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|August 14, 2008
概括
糖辅助结合 (SAL) 可使复杂的糖合成. 这项研究表明,SAL与扩展糖起作用,但C-3糖化阻断结合,指导未来的糖蛋白构造.
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
- 葡萄糖化学 葡萄糖化学
背景情况:
- 糖辅助结合 (SAL) 是一种用于融合糖合成的有价值的方法.
- 目前的SAL应用仅限于基于单糖的醇辅助剂.
- 将SAL扩展到复杂的,自然存在的甘氨酸对于合成先进的糖和糖蛋白质至关重要.
研究的目的:
- 为了研究SAL的可行性,复杂的多糖醇辅助剂.
- 为了确定C-3,C-4和C-6位置的糖化对SAL效率的影响.
- 为在复杂的糖和糖蛋白合成中使用SAL制定指导方针.
主要方法:
- 模型糖的化学酶合成,具有不同的糖化模式.
- 合成的葡萄糖与使用SAL方法的乙烯的反应.
- 基于基醇辅助剂上糖化酶的位置和程度的结合效率的分析.
主要成果:
- 盐酸对辅助含有甘氨酸的扩展糖化敏感.
- 结合在C-4和C-6位置的糖化中是成功的.
- 在C-3位置的糖基化完全抑制了SAL反应.
- 在C-4糖基化过程中,SAL的效率受到基的N端氨基酸的影响.
- 乙的C端残留物不会显著影响结合效率.
结论:
- 盐酸盐可以适应用于更复杂,扩展的糖结构.
- 在C-3处的糖化是防止SAL的关键因素,需要仔细选择结合部位.
- 了解这些限制,可以在复杂的糖和糖蛋白合成中战略地应用SAL.
- 这些发现为优化基于复杂碳水化合物合成的SAL产量提供了必要的指导.
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