Convergent total syntheses of (-)-rubriflordilactone B and (-)-pseudo-rubriflordilactone B

Mohammad M, Chintalapudi V, Carney J, Mansfield S, Sanderson P, Christensen K, Anderson E

A highly convergent strategy for the synthesis of the natural product (-)-rubriflordilactone B, and the proposed structure of (-)-pseudo-rubriflordilactone B, is described. Late stage coupling of diynes containing the respective natural product FG rings with a common AB ring aldehyde precedes rhodium-catalyzed [2+2+2] alkyne cyclotrimerization to form the natural product skeleton, with the syntheses completed in just one further operation. This work resolves the uncertainty surrounding the identity of pseudo-rubriflordilactone B, and provides a robust platform for further synthetic and biological investigations.

Keywords:

cyclotrimerization

,

schinorterpenoids

,

natural products

,

total synthesis

,

structure elucidation