Four new heptaketides, pseudonectrins A–D ( 1–4 ), and four known compounds ( 5–8 ) were isolated from cultures of an endophytic fungus Nectria pseudotrichia . Their structures were elucidated primarily by NMR experiments. The absolute configurations of 1–3 and 4 were assigned by electronic circular dichroism calculations and the modified Mosher method, respectively. Compound 1–3 showed moderate cytotoxicity, with IC _(50) values of 11.6–41.2 μM.
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