Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
J Org Chem. 2009 Nov 20;74(22):8810-3. doi: 10.1021/jo901793f.
A concise synthesis of a tetrahydropyran ring system corresponding to the C31-C40 and C43-C52 units of amphidinol 3 is described. Successive chemoselective reactions, i.e., cross-metathesis to differentiate the iodoolefin from the terminal olefin and Sharpless asymmetric dihydroxylation on the resulting E-olefin, resulted in expeditious synthesis of an intermediate that was then cross-coupled to afford an E,E-diene system. Four contiguous stereogenic centers were installed via construction of the tetrahydropyran ring by means of Katsuki-Sharpless asymmetric epoxidation, 6-endo-tet cyclization, and Sharpless asymmetric dihydroxylation.
描述了一种四氢吡喃环系统的简洁合成，该系统对应于 Amphidinol 3 的 C31-C40 和 C43-C52 单元。通过连续的选择性化学反应，即交叉复分解反应将碘烯烃与末端烯烃区分开，然后对生成的 E-烯烃进行 Sharpless 不对称双羟基化反应，快速合成了一个中间体，然后将其交叉偶联得到一个 E,E-二烯系统。通过 Katsuki-Sharpless 不对称环氧化、6-endo-tet 环化和 Sharpless 不对称双羟基化反应构建四氢吡喃环，引入了四个连续的手性中心。
