Asymmetric Total Syntheses of Communesin F and a Putative Member of the Communesin Family.

Here we report asymmetric total syntheses of communesin F and a putative member of the communesin family of bis-aminal alkaloid natural products. The successful strategy featured the invention of an asymmetric organocatalytic reaction to unify two oxindole subunits, a Ti(Oi Pr)4 -mediated dehydrative skeletal rearrangement, and a late-stage Pd(OAc)2 -catalyzed directed CH-alkenylation reaction. Collectively, the synthetic technologies disclosed herein enabled the preparation of a late-stage polycyclic intermediate catered for the synthesis of both naturally occurring and designed communesins. More importantly, speculated and yet to be discovered member(s) of the communesin family can now be accessed to facilitate a better understanding of the communesin biosynthetic network.