KULOLIDE - A CYTOTOXIC DEPSIPEPTIDE FROM A CEPHALASPIDEAN MOLLUSK, PHILINOPSIS-SPECIOSA

Kulolide, a cyclic depsipeptide, was isolated from a cephalaspidean mo llusk, Philinopsis speciosa Pease, 1860. Kulolide is made up of five a mino acid residues, one each of L-Ala, L-Pro, and N-Me-D-Val and two o f L-Val, and two carboxylic acids, L-3-phenyllactic acid and the unpre cedented (R)-3-hydroxy-2, 2-dimethyl-7-octynoic acid. The kulolide str ucture was elucidated by spectral techniques and hydrolytic reactions. Kulolide is active against L-1210 leukemia cells and P388 murine leuk emia cells at IC50 values of 0.7 and 2.1 mu g/mL, respectively. Kuloli de caused morphological change against rat 3Y1 fibroblast cells at the concentration of 50 mu M.