Total synthesis of ulongamide A, a cyclic depsipeptide isolated from marine cyanobacteria Lyngbya sp.

A total synthesis of ulongamide A (1), a cytotoxic natural cyclic depsipeptide, was achieved by a convergent route involving coupling of the fragments 7 and 8 to the pentapeptide 24, and subsequent cyclization thereof after prior removal of the t-Boc protecting groups.