Ligerin, an Antiproliferative Chlorinated Sesquiterpenoid from a Marine-Derived Penicillium Strain

A new chlorinated sesquiterpenoid analogue of fumagillin, ligerin (1), was isolated from a marine-derived strain of Penicillium, belonging to the subgenus Penicillium, along with the known compounds penicillic acid (2), orcinol, and orsellinic acid. Chemical structures were established by an interpretation of spectroscopic data including IR, UV, and HRESIMS, together with analyses of 1D and 2D NMR spectra and X-ray analysis for the determination of the absolute configuration. Ligerin (1) displayed strong inhibitory activity against an osteosarcoma cell line. This is the first report of the isolation of a fumagillin analogue from a marine-derived Penicillium strain.