Chem. Pharm. Bull. 55(9) 1316—1318 (2007)

and/or antioxidant secondary metabolites, for example, carneic acids A—B, cohaerins C—F, daldinins C—F, ramulosin, and sassafrins A—D. During our ongoing search for biologically active metabolites from the endophytic fungi, the broth extract of the xylariaceous fungus PSU-A80, isolated from the leaves of Garcinia atroviridis, showed the antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical assay. To search for antioxidant metabolites, the ethyl acetate extracts from the culture broth and cell of the xylariaceous fungus PSUA80 were subjected to various chromatographic separation. Three new compounds, one hypoxylonol, xylarenol (1), one hexadienoic acid, xylarenoic acid (2), and one tetralone, xylarenone (3), were isolated together with ten known compounds, hypoxylonol B (4), 8-methoxy-1-naphthol, ( )-5-methylmellein, ( )-6-hydroxymellein, isosclerone (5), tyrosol, (E,E)-4-hydroxymethyl-4,6-octadien-2,3diol, (E)-3-benzylidenehexahydro-2-methylpyrrolo[1,2-a]pyrazine-1,4-dione, (E)-3-benzylidenehexahydropyrrolo[1,2-a]pyrazine-1,4-dione, and trans-4-hydroxy-6-methyl3,4,5,6-tetrahydro-2H-pyran-2-one. The antioxidation activity of all isolates was performed in DPPH assay. This is also the first report on the isolation of (E)-3-benzylidenehexahydropyrrolo[1,2-a]pyrazine-1,4-dione and its Nmethyl derivative as natural products.