First Total Synthesis of the Bioactive Anthraquinone Kwanzoquinone C and Related Natural Products by a Diels–Alder Approach
作者:Lutz F. Tietze、Kersten M. Gericke、Carlos Güntner
DOI:10.1002/ejoc.200600634
日期:2006.11
cycloaddition.Diels–Alder reaction of 6 with the juglone derivative 5 gives the bis-benzyl-protected anthraquinone 4 after aromatization. Finally, glycosidation of the phenolic hydroxy group using 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl trichloroacetimidate followed by the cleavage of the benzyl ethers and the solvolysis of the acetate groups yields the natural product 1. A related anthraquinone natural
首次全合成新型抗癌剂宽唑醌 C (1),一种蒽醌糖苷,已从橙黄花菜 (Kaempfer) (Hemerocallisfulva) 的根提取物中分离出来。该策略涉及通过环丁酮 rac-11 的电环旋转开环制备四取代的 1,3-丁二烯 6,环丁酮 rac-11 是通过 [2+2] 环加成获得的。 6 与胡桃酮衍生物 5 的 Diels-Alder 反应芳构化后得到双苄基保护的蒽醌4。最后,使用 2,3,4,6-四-O-乙酰基-α-D-吡喃葡萄糖基三氯乙酰亚胺酯对酚羟基进行糖苷化,然后裂解苄基醚和溶剂解乙酸酯基团,得到天然产物 1。以1,3-丁二烯17和胡桃酮衍生物16为底物,获得了具有抗氧化作用的蒽醌类天然产物2。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)