New facile enantio- and diastereo-selective syntheses of (-)-triptonide and (-)-triptolide.

A novel formal asymmetric synthesis of (-)-triptonide and (-)-triptolide, featuring a new alternative access to their known key intermediate 4, has been achieved through two synthetic routes in 9 steps with 13.6% total yield and 10 steps with 18.5% overall yield, respectively. This synthesis is scalable and hence has high potential for application to further synthetic elaboration and biologic investigation on such natural products.