Four New Highly Oxygenated Eremophilane Sesquiterpenes from an Endophytic Fungus Isolated from .

Four new eremophilane-type sesquiterpenes, boeremialanes A-D (-) were obtained from solid substrate cultures of (Didymellaceae), an endophytic fungus isolated from (Liliaceae). Boeremialanes A-C (-) are highly oxygenated eremophilanes with a benzoate unit attached at the C-13 position and are rarely found in nature. Their structures and absolute configurations were determined by extensive spectroscopic methods, electronic circular dichroism (ECD), and nuclear magnetic resonance (NMR) calculations with DP4+ analysis. Boeremialane D () potently inhibited nitric oxide production in lipopolysaccharide-treated RAW264.7 macrophages with an IC of 8.62 μM and was more potent than the positive control, pyrrolidinedithiocarbamate (IC = 23.1 μM).