Progress towards the total synthesis of hamigerans C and D: a direct approach to an elaborated 6-7-5 carbocyclic core
The hamigeran family of natural products has been the target of numerous synthetic efforts because of its biological activity and interesting structural properties. Herein, we disclose our efforts toward the synthesis of hamigerans C and D, unique among the initially isolated members because of their 6-7-5 carbocyclic core. Our approach directly targets this tricyclic motif by sequential Negishi and Heck coupling reactions, yielding an advanced intermediate with all necessary carbons and sufficient functionality poised for completion of the synthesis of these two natural products.
Additional Information© 2017 Japan Antibiotics Research Association. Received 8 June 2017; revised 3 July 2017; accepted 6 July 2017. Online publication, 6 September 2017. Dedicated to Prof K. C. Nicolaou for his tremendous scientific contributions to the total synthesis of highly complex and biologically important natural products. We thank NIH-NIGMS (R01GM080269) for supporting this research. DCD would like to thank the NSF (predoctoral research fellowship, No. DGE-1144469) and Caltech for financial support. Dr David VanderVelde (Caltech) is thanked for aid in NMR structural determination. Dr Allen Hong and Dr Scott Virgil are thanked for helpful discussions. The authors declare no conflict of interest.
Supplemental Material - ja201796x1.pdf