使用糖的立体选择性催化O-糖化
Hahn Kim1, Hongbin Men, Chulbom Lee
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Journal of the American Chemical Society
|February 5, 2004
概括
一种新的催化反应有效地产生具有高立体选择性的复杂分糖. 连接物选择控制了阿尔法或β糖化物是否形成,在碳水化合物化学中提供了多功能合成路径.
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
- 催化剂是一种催化剂.
背景情况:
- 传统的糖化方法往往缺乏立体控制或需要恶劣的条件.
- 开发高效和立体选择性的合成复杂碳水化合物的方法对于各种应用至关重要.
研究的目的:
- 开发一种高度立体选择的催化O-糖化反应.
- 通过连接体选择来证明对异构立体化学的控制.
- 为了展示由此产生的糖化物在进一步的合成转化中的实用性.
主要方法:
- 在催化下,甘氨酸酸或碳酸盐与 (II) 氧化物的反应.
- 利用不同的素连接物 (2-di-tert-butylphosphinobiphenyl与三甲基酸盐) 来影响立体化学结果.
- 随后通过二化,水化和化对糖酸盐产品进行功能化.
主要成果:
- 在分糖化形成中取得了良好的产量和高立体选择性.
- 证明了与2-di-tert-butylphosphinobiphenyl连接体的排他性β-糖化物形成.
- 展示了与三甲基酸连接体的偏好的α-anomer形成.
- 成功地对不和葡萄糖酸进行了进一步的转化.
结论:
- 开发的催化O-糖化提供了一种新的,温和的,简单的合成复杂碳水化合物的方法.
- 对异构立体化学的联体控制为合成碳水化合物化学提供了强大的工具.
- 该方法通过结合的糖化和功能化策略,可以访问具有挑战性的糖结构.
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