Purealidin S and Purpuramine J, Bromotyrosine Alkaloids from the Fijian Marine Sponge Druinella sp.

Abstract
Two bromotyrosine alkaloids, purealidin S (2) and purpuramine J (5), were isolated from the Fijian marine sponge Druinella sp. Eight known bromotyrosine compounds were also isolated. This is the first report of a bromotyrosine N-oxide containing alkaloid. These two compounds were found to have moderate cytotoxic activity. In addition, bioassay data for the eight known bromotyrosine metabolites are reported.