Gram-Scale Access to (3,11)-Cyclotaxanes-Synthesis of 1-Hydroxytaxuspine C

Herein, we present the semisynthesis of complex taxane diterpenoid 1-hydroxytaxuspine C. Starting from cheap and abundant 10-deacetylbaccatin III, a scalable and robust route was developed, enabling an unprecedented gram-scale access to the intricate (3,11)-cyclotaxane scaffold. In addition, this represents the first synthetic access to C1-hydroxylated cyclotaxanes. The natural product is synthesized in 17 steps, with the reactions being performed on decagram-scale up to an advanced intermediate, establishing the scalability of this approach.