Absolute Configuration and Total Synthesis of (+)-Curacin A, an Antiproliferative Agent from the Cyanobacterium <i>Lyngbya majuscula</i>
作者:James D. White、Tae-Seong Kim、Mitch Nambu
DOI:10.1021/ja9629874
日期:1997.1.1
The absolute configuration of curacin A was determined as (2R,13R,19R,21S)-1 by comparison of degradation products 2 and 3 with the same materials prepared by asymmetric synthesis. The total synthesis of 1 was completed from (1R,2S)-2-methylcyclopropanecarboxylic acid (8) and the amino alcohol derivative 46. The latter was prepared from 4-pentynal (14) and the Garner aldehyde (43). Asymmetric allylation
通过将降解产物 2 和 3 与通过不对称合成制备的相同材料进行比较,确定 curacin A 的绝对构型为 (2R,13R,19R,21S)-1。1的全合成由(1R,2S)-2-甲基环丙烷羧酸(8)和氨基醇衍生物46完成。后者由4-戊醛(14)和加纳醛(43)制备。14 的不对称烯丙基化,然后衍生的醇 16 的甲基化得到 17,将其进行锆化-碘化得到 18。后者与硼酸乙烯酯 21 偶联,后者由乙酸 4-戊炔酯 (20) 制备,在Pd(0)和所得三烯醇22被转化为碘化鏻24。来自24的叶立德与43的Wittig反应提供四烯44,其在甲醇分解时产生45。