A Sterol and Spiroditerpenoids from a Penicillium sp. Isolated from a Deep Sea Sediment Sample

A new polyoxygenated sterol, sterolic acid (1), three new breviane spiroditerpenoids, breviones I–K (2–4), and the known breviones (5–8), were isolated from the crude extract of a Penicillium sp. obtained from a deep sea sediment sample that was collected at a depth of 5115 m. The structures of 1–4 were elucidated primarily by NMR experiments, and 1 was further confirmed by X-ray crystallography. The absolute configurations of 2 and 3 were deduced by comparison of their CD spectra with those of the model compounds. Compounds 2 and 5 showed significant cytotoxicity against MCF-7 cells, which is comparable to the positive control cisplatin.