Nagelamides A−H, New Dimeric Bromopyrrole Alkaloids from Marine Sponge <i>Agelas</i> Species

Abstract

Eight new dimeric bromopyrrole alkaloids, nagelamides A-H (1-8) and a monomeric one, 9,10-dihydrokeramadine (9), have been isolated from the Okinawan marine sponge Agelas sp., and the structures were elucidated from spectroscopic data. Nagelamides A-H (1-8) exhibited antibacterial activity against Gram-positive bacteria. Nagelamide G (7) inhibited protein phosphatase 2A activity.