Four Caribbean Agelas sponges (A. clathrodes, A. conifera, A. dispar. A. longissima) have been investigated for the alkaloid composition. Along with a series of known bromopyrrole alkaloids, two related novel compounds of this class, dispacamides C (7) and D (8), were found and their structures determined with spectroscopic methods. All the isolated Agelas bromopyrrole alkaloids have been evaluated for the antihistaminic activity on the guinea pig ileum. (C) 1997 Elsevier Science Ltd.