Divergent Total Syntheses of (−)-Daphnilongeranin B and (−)-Daphenylline

(−)-Daphnilongeranin B and (−)-daphenylline are two hexacyclic Daphniphyllum alkaloids, each containing a complex cagelike backbone. Described herein are the first asymmetric total synthesis of (−)-daphnilongeranin B and a bioinspired synthesis of (−)-daphenylline with an unusual E ring embedded in a cagelike framework. The key features include an intermolecular [3+2] cycloaddition, a late-stage aldol cyclization to install the F ring of daphnilongeranin B, and a bioinspired cationic rearrangement leading to the tetrasubstituted benzene ring of daphenylline.