State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, People's Republic of China.
J Org Chem. 2011 May 20;76(10):3946-59. doi: 10.1021/jo2003852. Epub 2011 Apr 29.
An accelerated, enantioselective, and general synthetic route to a class of malyngamides, K (1), L (3), and 5''-epi-C (4), bearing a cyclohexenone ring or a heavily oxygenated six-membered ring and a vinyl chloride structural motif was developed. The key step was the Suzuki cross-coupling reaction of boronic acids 6-8 with unsaturated carboxylic amides 5a,b possessing the chlorovinyl iodide functionality for the construction of the skeletons of 1-4. The key intermediates 10a,b were prepared using Ogilvie's method for the construction of the chlorovinyl iodide functionality. The NMR data of the synthetic compound 2 were in full agreement with those of the reported product, and the discrepancy in the specific rotation data suggested that the correct structure of malyngamide L should be 3, in which the absolute configuration of the amine part was enantiomeric to that in compound 2. Then the absolute configuration of the stereogenic center at C(3'') and C(4'') in malyngamide L was confirmed by synthesis of compound 3.
开发了一种快速、对映选择性和通用的合成路线，用于合成一类具有环己烯酮环或高度含氧的六元环和乙烯基氯结构基序的马缨丹酰胺 K(1)、L(3)和 5''-表-C(4)。关键步骤是硼酸 6-8 与不饱和羧酸酰胺 5a,b 的 Suzuki 交叉偶联反应，后者具有氯代乙烯基碘化物官能团，用于构建 1-4 的骨架。关键中间体 10a,b 是使用 Ogilvie 方法制备的，用于构建氯代乙烯基碘化物官能团。合成化合物 2 的 NMR 数据与报道产物完全一致，旋光度数据的差异表明马缨丹酰胺 L 的正确结构应为 3，其中胺部分的绝对构型与化合物 2 对映。然后通过合成化合物 3 确定了马缨丹酰胺 L 中 C(3'')和 C(4'') 立体中心的绝对构型。
