关于全合成Azadirachtin的模型研究

Wedelolactone is a natural product and is one kind of derivatives of Coumestan. Wedelolactone has high bioactivity. Although there are many reports about the synthesis of Coumestan and its derivatives in literature, all these synthesis methods are to specific molecules and there is almost no report about the total synthesis of Wedelolactone. So we designed a more general and efficient synthesis route, which is not only used in the total synthesis of Wedelolactone, but also can be used in the synthesis of other derivatives of Coumestan. We synthesized segment A and B convergently using 3,4-dihydroxybenzyl aldehyde and 2,4,6-trihydroxybenzyl aldehyde as starting materials separately, and then finished the total synthesis of Wedelolactone firstly through two key reactions: Sonogashira coupling and Carbonative Annulation. The total yield is 53% from the longest synthesis route (9 steps).

Wedelolactone是一类叫做Coumestan衍生物中的一种天然产物，中文名为蟛其菊内酯，具有很高的生物活性。文献中，虽然对Coumestan其它衍生物的合成有许多报道，但这些合成路线都是针对具体分子而言的;而且对Wedelolactone全合成的报道几乎没有。因此，我们设计了一条比较general and efficient 的路线，不仅能用于Wedelolactone的全合成，也能应用于Coumestan其它衍生物的合成。我们分别以3，4-二羟基苯甲醛和2，4，6-三羟基苯甲醛为原料，会聚式地合成片段A和片段B，通过两关键反应：Sonogashira Coupling 和 Carbonative Annulation 第一次完成了Wedelolactone的全合成，以最长的合成步骤（9步）来计算，全合成总产率为53%。