Somamides A and B, two new depsipeptide analogues of dolastatin 13 from a Fijian cyanobacterial assemblage of Lyngbya majuscula and Schizothrix species.

Somamides A (1) and B (2) were isolated from assemblages of the marine cyanobacteria Lyngbya majusculaand Schizothrix sp. from the Fijian Islands. These new depsipeptides are analogous in structure to the cyanobacterial metabolite symplostatin 2 (4) as well as dolastatin 13 (3), originally isolated from Dolabella auricularia, further demonstrating the cyanobacterial origin of the dolastatins.