本文描述了我们最近对用于糖基化反应的糖基亚磷酸酯的研究,特别强调了保护基团和立体化学对异头反应性和立体选择性的影响的研究,以及该方法在合成 Lewis X (Lex)、Lewis Y 中的应用(Ley)、糖肽和唾液酸路易斯 X (SLex) 模拟物。发现 α-O-岩藻糖基-l-苏氨酸和 α-O-岩藻糖基-(1R,2R)-2-氨基环己醇都是 SLex 模拟物化学/酶促合成的有效模板,制备的一些岩藻肽是 5-10作为 E-选择素抑制剂的活性比 SLex 高出数倍。
The use of Aspergillus terreus extracts in the preparative synthesis of 2-keto-3-deoxy-ulosonic acids
摘要:
Pure 2-keto-3-deoxy-ulosonic acids, KDGal (1), DAH (2) and its 5-epimer (3) were prepared on preparative scales through diastereoselective aldol reactions of pyruvate respectively with D-glyceraldehyde, D-erythrose and D-threose, catalyzed by Aspergillus terreus extracts; from 2-deoxy-D-ribose, 5-deoxy-KDO (4) could be obtained in a lower yield, with a diastereomeric excess of 72%.