The Berkeleyacetals, Three Meroterpenes from a Deep Water Acid Mine Waste Penicillium

Berkeley Pit Lake is a 1500 ft deep abandoned open-pit copper mine filled with over 1140 billion liters of acidic, metal-sulfate-contaminated water. This harsh environment is proving to be a source of unusual microorganisms that produce novel bioactive compounds. We recently reported the structures of berkeleydione (1) and berkeleytrione (2), two novel hybrid polyketide-terpenoid metabolites isolated from a deep water Penicillium sp. growing in Berkeley Pit Lake. In this paper we report the structures of three new compounds, berkeleyacetals A–C (3–5) isolated from extracts of this fungus. The structures of these compounds were deduced by comparison of mass spectral and NMR data to that of berkeleydione (1).