New 19-oxygenated and 4-methylated steroids from the Formosan soft coral Nephthea chabroli

Chemical investigation of the Formosan soft coral Nephthea chabroli resulted in the isolation of four new 19-oxygenated steroids, nebrosteroids I–L (1–4), together with a new 4α-methylated steroid, nebrosteroid M (5). The molecular structures of these isolated metabolites were elucidated on the basis of extensive spectroscopic analysis and by comparison of the data with those of related metabolites. Compounds 1–5 were evaluated for anti-inflammatory activity using RAW 264.7 macrophages.