Terretonin O: a new meroterpenoid from .

Terretonin O (), a new meroterpenoid, was isolated individually from both methanolic extracts of thermophilic TM8 and marine LGO13. The recently reported terretonins M () and N ( were further isolated from the fungus LGO13 along with nine known compounds, terrelumamide A (), terrein (), methyl-3,4,5-trimethoxyl-2-[2-(nicotinamide)benzamido] benzoate (), butyrolactones I-III (-), aspulvinone O (), ergosterol, ergost-4-ene-3-one and methyl linoleate. Structure of terretonin O () was established on the bases of HRESIMS, 1D and 2D NMR spectra and comparison with its analogues in literatures. The relative stereochemistry of was assigned on the basis of NOESY spectra and comparison with reported configuration of its congener compounds and . The antimicrobial and cytotoxic activities of the fungal extracts and obtained compounds were assayed using a set of microorganisms, and cervix carcinoma cell line (KB-3-1), respectively. Isolation and taxonomical characterization of the producing strains are reported.