The hasubanan and acutumine alkaloids are a large family of botanical metabolites that share a common tetracyclic skeleton.  To date, nearly 100 members of this family have been isolated. Various hasubanan and acutumine alkaloids exhibit diverse biological effects, ranging from narcotic antagonist, anti-viral activities, to memory-enhancing effects.  We have developed chemistry that allows access to a wide array of hasubanan and acutumine structures.  Our synthetic route features the application of 5-trimethylsilylcyclopentadiene as an easily-removable, stabilizing, stereocontrol element.  By this approach, we have prepared ten hasubanan alkaloids and two acutumine alkaloids, in 5–14 steps from the common precursor 1.

Seth B. Herzon, Nicholas A. Calandra, and Sandra M. King Angew. Chem., Int. Ed. 2011, 50, 8863.

Sandra M. King, Nicholas A. Calandra, and Seth B. Herzon Angew. Chem., Int. Ed. 2013, 52, 3642.

Nicholas A. Calandra, Sandra M. King, and Seth B. Herzon J. Org. Chem. 2013, 78, 10031.

For a review, see:

Sandra M. King and Seth B. Herzon, Hasubanan and Acutumine Alkaloids.  In The Alkaloids: Chemistry and Biology, Hans-Joachim Knölker, Ed.; Elsevier: Boston, 2014, Vol. 73, p. 161.