Pentacydic core

Fries, J.L., Jeffrey, C.S., and Sorensen, E.J. (2009) A hypervalent iodine-induced double annulation enables a concise synthesis of the pentacydic core structure of the cortistatins. Oig. Lett., 11, 5394-5397. 

Fishlock, D. and Williams, R.M. (2008) Synthetic studies on ET-743. Assembly of the pentacydic core and a formal total synthesis. /. Org. Chem., 73,9594-9600. 

Ebine, M., Fuwa, H., and Sasaki, M. (2008) Total synthesis of (—)-brevenal a concise synthetic entry to the pentacydic polyether core, Org. Lett., 10, 227S-227S. 

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