作者:Hui Ming Ge、Lan-De Zhang、Ren Xiang Tan、Zhu-Jun Yao
DOI:10.1021/ja305261h
日期:2012.8.1
The first total synthesis of (-)-lannotinidine B, a unique tetracyclic constitutent of Lycopodium annotinum, has been accomplished in 10 steps with 23% overall yield. The completed short and efficient synthesis is characterized with three highly chemo- and/or stereoselective reductive-amination steps to furnish the desired trans-fused 6/6 bicycle and the aza seven-membered ring system, and a direct intramolecular acyloin condensation to deliver the cyclopentanone moiety, as well as successful application of a protecting group-free strategy and an optimal redox order.