Su Qibin, Dakin Les A, Panek James S
Department of Chemistry and Center for Chemical Methodology and Library Development, Metcalf Center for Science and Engineering, 590 Commonwealth Avenue, Boston University, Boston, Massachusetts 02215, USA.
J Org Chem. 2007 Jan 5;72(1):2-24. doi: 10.1021/jo0610412.
Complete details of an asymmetric synthesis of leucascandrolide A (1) are described. The synthesis highlights the use of two diastereoselective [4 + 2]-annulations for the assembly of the functionalized bispyranyl macrolide 3. An efficient assembly and union of the oxazole-containing side chain 4 with macrolide 3 was carried out using a Mitsunobu reaction. A convergent route to the oxazole side chain was developed using a Sonogashira cross-coupling between 2-trifloyloxazole 16 and alkyne 17, which allowed for the installation of the C9'-C10' (Z)-olefin.
本文描述了白海绵内酯A（1）不对称合成的完整细节。该合成突出了使用两个非对映选择性[4 + 2]环化反应来构建官能化双吡喃基大环内酯3。通过Mitsunobu反应实现了含恶唑侧链4与大环内酯3的高效组装和连接。利用2-三氟甲磺酰氧基恶唑16与炔烃17之间的Sonogashira交叉偶联反应，开发了一条通向恶唑侧链的汇聚路线，该反应能够引入C9'-C10'（Z）-烯烃。
