A convergent approach to cyclopeptide alkaloids: Total synthesis of Sanjoinine G1

A general strategy for the synthesis of cyclopeptide alkaloids containing an endocyclic arylalkyl ether bond has been developed featuring a key intramolecular SNAr reaction. The importance of the N-terminal protective group in the realization of such a strategy is documented. From the appropriate amino acid constituents, the natural sanjoinine G1, a 14-membered para cyclophane, has been synthesized in seven steps with 21% overall yield.