Facile Construction of the Pentacyclic Framework of Subincanadine B. Synthesis of 20-Deethylenylated Subincanadine B and 19,20-Dihydrosubincanadine B
作者:Yanqin Liu、Shengjun Luo、Xingnian Fu、Fang、Zeyang Zhuang、Wanting Xiong、Xueshun Jia、Hongbin Zhai
DOI:10.1021/ol0526367
日期:2006.1.1
We describe a facile approach for effectively constructing the pentacyclic framework of subincanadine B. The seven-step assembly of tetracyclic ketone 14 featured Michael addition, Pictet-Spengler cyclization, and Dieckmann condensation. From this key ketone intermediate, two analogues of subincanadine 13, i.e., 20-deethylenylated subincanadine B (27) and 19,20-dihydrosubincanadine B (31), were synthesized in four steps, respectively.