Dominicin, a cyclic octapeptide, and laughine, a bromopyrrole alkaloid, isolated from the Caribbean marine sponge Eurypon laughlini

Dominicin, a new cyclic peptide, and the new bromopyrrole alkaloid laughine (4) have been isolated from the marine sponge Eurypon laughlini collected in Dominica. The structures of 1 and 4 were determined by a combination of spectroscopic analysis and chemical degradation. Single-crystal X-ray diffraction analysis confirmed the structure of dominicin (1).