Frajunolides L-O, four new 8-Hydroxybriarane diterpenoids from the Gorgonian Junceella fragilis

Four new 8-hydroxybriarane diterpenoids, frajunolides L-O (1-4), were isolated from the Taiwanese gorgonian Junceella fragilis. The structures of compounds 1-4 were elucidated based on spectroscopic analysis, especially 2D NMR ((1)H-(1)H COSY, HSQC, HMBC and NOESY) and HRMS. Compounds 1 and 4 showed weak anti-inflammatory activity as tested by superoxide anion generation and elastase release by human neutrophil in response to fMLP/CB. Compound 3 showed selective inhibition on elastase release in vitro.