Kerl Thomas, Berger Florian, Schmalz Hans-Günther
Department of Chemistry, University of Cologne, Greinstrasse 4, 50939, Köln, Germany.
Chemistry. 2016 Feb 24;22(9):2935-8. doi: 10.1002/chem.201505118. Epub 2016 Jan 27.
The first total synthesis of houttuynoid B, a powerful antiviral flavonoid glycoside from the Chinese plant Houttuynia cordata, is described. In a key step, a Baker-Venkataraman rearrangement employing an already glycosylated substrate was used to efficiently set up the fully functionalized carbon skeleton. The required benzofuran building block was prepared through a domino Sonogashira coupling/5-endo-dig cyclization and converted into a stable 1-hydroxybenzotriazole-derived active ester prior to linking with a galactosylated hydroxyacetophenone unit. The elaborated synthesis requires only nine steps (11 % overall yield) along the longest linear sequence and paves the way for the preparation of structurally related compounds for further biological evaluation.
本文描述了从中国植物鱼腥草中提取的具有强大抗病毒活性的黄酮糖苷——鱼腥草素B的首次全合成。在关键步骤中，采用已糖基化的底物进行贝克-文卡塔拉曼重排，以有效地构建完全官能化的碳骨架。所需的苯并呋喃结构单元通过多米诺索诺加希拉偶联/5-内型-环化反应制备，并在与半乳糖基化的羟基苯乙酮单元连接之前转化为稳定的1-羟基苯并三唑衍生的活性酯。精心设计的合成路线沿着最长线性序列仅需九步（总产率11%），为制备结构相关化合物以进行进一步的生物学评估铺平了道路。
