New chlorinated peptides from the tropical marine sponge Dysidea sp.

Five new chlorinated peptides (5)– (9) have been isolated from a Dysidea sp. and identified by two-dimensional NMR spectroscopy. The absolute stereochemistry of the metabolites was deduced by chemical correlation with S-(−)-4,4,4-trichloro-3-methylbutanoic acid (10) and with an alcohol (11).