Two previously unreported compounds, designated pyrrole-2, 5-dione xylogonone acids A (1) and B (2), were isolated from the ascomycete fungus Xylogone Sphaerospora. These metabolites feature a rare, highly functionalized pyrrole-2,5-dione. Their chemical structures were determined through detailed analysis of NMR and HRMS data, with the structure of compound 1 further validated by X-ray crystallographic analysis. Both compounds exhibited distinct cytotoxic profiles against several human cancer cell lines, including A549, MDA-MB-231, HepG2, HT-29, K562, and SW620, with IC50 values ranging from 3.76 to 72.43 µM for compound 1 and 7.97 to 68.46 µM for compound 2.