A new nitrogenous metabolite with a p-terphenyl core, sarcodonin (3), has been isolated from fruiting bodies of the basidiomycete Sarcodon leucopus. The structure of 3 was determined through a careful study of its peracetate 4, by use of an array of spectroscopic techniques (including (15)N NMR, gradient-enhanced, and reverse-detected 2D NMR experiments) and chemical degradation. ROESY data and molecular mechanics (MM+) calculations led to assignment of the absolute configuration of 4. Compound 3 exhibited moderate cytotoxicity against KB and P-388 tumor cell cultures.