Total Synthesis of (+)-Haperforin G

A concise chemical synthesis of (+)-haperforin
G in 20 steps from
commercially available starting materials is achieved with the integration
of the Co-catalyzed intramolecular Pauson–Khand reaction for
the stereoselective construction of cyclopentanone bearing an all-carbon
quaternary stereogenic center at the bridge-head position and the
light-initiated photocatalysis for convergent and asymmetric cross-coupling
of the unstabilized C­(sp3)-radical with an enone. The developed
chemistry paves the way to synthesizing structurally diverse analogs
of haperforin G (6).