Krempfielins J-M, new eunicellin-based diterpenoids from the soft coral cladiella krempfi

New four eunicellin-based diterpenoids, krempfielins J-M (1-4) were isolated from the organic extract of a Taiwanese soft coral Cladiella krempfi. The structures of the new metabolites were elucidated on the basis of extensive spectroscopic analysis. The structure of compound 2 is rare due to the presence of the highly oxygenated pattern. Anti-inflammatory activity of 1-6 to inhibit the superoxide anion generation and elastase release in FMLP/CB-induced human neutrophils was also evaluated, and 2 and 4 were shown to possess the ability to inhibit the elastase release.