Bioactivity-directed fractionation from the seeds of Annona cherimolia resulted in the isolation of two known cytotoxic compounds : corrosolin (1) and compound-2 (2). The structures of these compounds were characterized on the basis of chemical and spectral data. Corrosolin has a relative stereochemical relationship of threo/trans/threo for the mono-tetrahydrofuran (THF) ring with two flanking hydroxyls, from C-15 to C-20, which is the annonacin type. Compound-2 has a relative stereochemical relationship of threo/trans/threo/trans/threo for the adjacent bis-THF ring with two flanking hydroxyls, such as in the asimicin type. The absolute configurations of carbinol carbons in corrosolin in corrosolin were determined as 10R, 15R, and 20R by analysis of its Mosher ester derivatives. Corrosolin and compound-2 are known, but are first isolated in this plant.