Construction of key building blocks towards the synthesis of cortistatins

This work reports the contruction of the key building blocks towards the synthesis of cortistatins; a family of steroidal alkaloids. Cortistatin A, being a primary target due to its superior biological properties over other congeners, has been approached by two different synthetic routes. Synthesis of the precursor to the heavily substituted A-ring starting from D-glucose and construction of the DE-ring junction employing Hajos-Parrish ketone as a chiral pool have been demonstrated. Efforts are underway to assemble these key fragments and build towards the total synthesis of cortistatin A