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).