Total Synthesis and Biological Evaluation of (+)-Gambieric Acid A and Its Analogues
作者:Kazuya Ishigai、Haruhiko Fuwa、Keisuke Hashizume、Ryo Fukazawa、Yuko Cho、Mari Yotsu-Yamashita、Makoto Sasaki
DOI:10.1002/chem.201204303
日期:2013.4.22
thus obtained closed the F‐ring and completed the polycyclic ether skeleton. Finally, the J‐ring side chain was introduced by using a Julia–Kocienski olefination in the presence of CeCl3 to complete the total synthesis of gambieric acid A (1), thereby unambiguously establishing its complete stereostructure. The present total synthesis enabled us to evaluate the antifungal and antiproliferative activities
在这项研究中,我们详细报告了冈比亚酸A(一种有效的抗真菌多环醚代谢物)的首次总合成和完整的立体结构。A / B环外环烯醇醚32是通过B环乙烯基碘18与烷基硼酸酯33的Suzuki-Miyaura偶联反应制备的,随后通过使用非对映选择性溴醚化作为关键转化来封闭A环。Suzuki-Miyaura将32与乙酸酯衍生的烯醇磷酸酯49偶联,然后将衍生的二烯进行开环易位,产生了D环。随后通过混合硫代缩醛化作用封闭C环,完成了A / BCD环片段的合成8。A / BCD和F'GHIJ环片段(即8和9)是通过Suzuki-Miyaura偶合组装的。通过利用七元F'环的内在构象特性,对C25立体生成中心进行了阐述。F'环被氧化裂解后,E环形成为环状混合硫缩醛(即70),然后使用糖基化化学方法进行立体选择性烯丙基化。由此获得的二烯3的闭环复分解反应关闭了F环并完成了多环醚骨架。最后,在存在CeCl 3的情况下