Total Synthesis Provides Strong Evidence: Xestocyclamine A is the Enantiomer of Ingenamine.

ABSTRACT: Xestocyclamine A ((-)-1) is featured prominently in a biosynthesis pathway leading to a large family of polycyclic alkaloids. The first total synthesis now proves that the structure of this compound had originally been misassigned. The route to (-)-1 is based on a double Michael addition for the formation of the bridged diazadecalin core and a palladium-catalyzed decarboxylative allylation to install the quaternary bridgehead center. Ring-closing alkyne metathesis allowed a 13-membered cycloalkyne to be forged, which was selectively reduced during an involved sequence of hydroboration/selective protodeborylation/alkyl-Suzuki coupling used to close the 11-membered ring. Crystallographic data prove the identity of synthetic (-)-1 with nominal xestocyclamine, but the spec

SUBMITTER: Meng Z 

PROVIDER: S-EPMC7467676 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature