Synthesis of 6-6-6 ABE tricyclic ring analogues of methyllycaconitine

摘要

A new synthesis of the bridged [6-6-6] ABE tricyclic ring analogues of methyllycaconitine with the C-1 oxygenated substituents has been developed using an efficient aza-annulation of β-enamino ketone followed by a facile decarboxylation to form BE rings.Subsequent elaboration to form the A ring was achieved by a transannular acyl radical cyclization with concomitant equipment of the key C-1 oxygen functionality.