Patellins 1-6 and trunkamide A: Novel cyclic hexa-, hepta- and octa-peptides from colonial ascidians, Lissoclinum sp

Patellins 1-5 have been isolated from the colonial ascidian Lissoclinum patella from Viti Levu, Fiji. Patellins 1 and 2 are cyclic hexapeptides, while patellins 3-5 are cyclic octapeptides. Two of these peptides (patellins 3 and 5), a new cyclic octapeptide (patellin 6), a new cyclic heptapeptide (trunkamide A), and the known metabolite lissoclinolide have also been isolated from a Lissoclinum sp. collected on the Great Barrier Reef, Australia. All structures were determined by high-field n.m.r. and mass spectroscopic methods, and by h.p.l.c. analysis of the constituent amino acids after hydrolysis of the peptides and derivatization according to Marfey's procedure.