Cytotoxic and anti-inflammatory cembranoids from the Vietnamese soft coral Lobophytum laevigatum

Four new cembranoids, namely laevigatol A-D (1-4), and six known metabolites (5-10), were isolated from the Vietnamese soft coral Lobophytum laevigatum. The structures of these compounds were elucidated by extensive spectroscopic analyses, and the absolute stereochemistry of 1 was determined using the modified Mosher's method. Compounds 5, and 7-10 exhibited cytotoxic activity against selected human cancer cell lines. Compounds 1, 2, 8, and 9 showed dose-dependent inhibitory effects on the TNF alpha-induced NF-kappa B transcriptional activity in Hep-G2 cells. Moreover, compounds 1, 2, 8, and 9 significantly inhibited the induction of COX-2 and iNOS mRNA dose-dependently, indicating that these compounds attenuated the synthesis of these transcripts at the transcriptional level. (C) 2011 Elsevier Ltd. All rights reserved.