Cytotoxic compounds from Laurencia pacifica

BACKGROUND: The current investigation sought to explore the nature of the secondary metabolites in the algae, Laurencia pacifica. RESULTS: This report details the first isolation of the sesquiterpenes isoaplysin (1), isolaurenisol (2), debromoisolaurinterol (3), debromoaplysinol (4), laur-11-en-10-ol (5), 10?-hydroxyldebromoepiaplysin (6), and the previously unknown 10-bromo-3,7,11,11-tetramethylspiro[5.5]undeca-1,7-dien-3-ol (7) from the algae, Laurencia pacifica. Isoaplysin (1) and debromoaplysinol (4) showed promising levels of growth inhibition against a panel cancer-derived cell lines of colon (HT29), glioblastoma (U87, SJ-G2), breast (MCF-7), ovarian (A2780), lung (H460), skin (A431), prostate (Du145), neuroblastoma (BE2-C), pancreas (MIA), murine glioblastoma (SMA) origin with average GI(50) values of 23 and 14 ?M. CONCLUSIONS: Isoaplysin (1) and debromoaplysinol (4) were up to fourfold more potent in cancer-derived cell populations than in non-tumor-derived normal cells (MCF10A). These analogues are promising candidates for anticancer drug development. [Figure: see text]