用于合成含有基本的α-或β-脱氧氨基糖酸的一般方法
Kevin M Hoang1, Nicholas R Lees1, Seth B Herzon1,2
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
这项研究引入了一种用基本合成甘氨酸的新方法,克服了易斯酸促进剂的挑战. 新的还原性化策略有效地产生具有高立体选择性的各种氨基糖衍生物.
科学领域:
- 有机化学
- 碳水化合物化学
- 合成方法
背景情况:
- 合成含糖的传统方法受到易斯酸促进剂协调问题的阻碍.
- 由于没有C2替代剂,氨基糖化物通常会产生二聚体混合物.
- 需要一种通用和立体选择性方法来合成含有基本的O-糖化物.
研究的目的:
- 开发一种新的合成策略,用于获取α-或β- 2,3,6-三氧化-3-氨基和2,4,6-三氧化-4-氨基O-糖化物.
- 将这种方法应用于各种重要的氨基糖衍生物的合成,包括胺,胺,胺和胺.
- 在低温下研究受替剂定向影响的立体化学结果.
主要方法:
- reductive lithiation of thiophenyl glycoside donors. 降低基因的化 基因的化 基因的化
- 用二甲基四胺过氧化物捕获生成的异构离子.
- 使用初级和二级过氧化物作为各种氨基糖合成的电友.
主要成果:
- 在60-96%的产量中成功合成α链氨基糖化物,选择性>50:1.
- 合成β结合的氨基糖化物,获得45- 94%的产量,具有1. 7->50:1的立体选择性.
- 与赤道替代剂相比,轴性氨基替代剂在低温下有利于β产物形成.
结论:
- 已经制定了一种具有基本的O-糖化物合成的通用和有效策略.
- 该方法为α和β结合的氨基糖提供了高产量和优异的立体选择性.
- 这种方法为获得药物化学和糖生物学相关的复杂氨基糖衍生物提供了有价值的工具.
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