Antineoplastic agents. 575. The fungus Aspergillus phoenicis

Cancer cell line bioassay-guided separation of an extract from the fungus Aspergillus phoenicis collected in Saskatchewan, Canada, resulted in the isolation of three new constituents designated asperlactone (1), aspergillol A (2), and aspergillol B (3), accompanied by four previously known constituents: asperic acid (4), hexylitaconic acid (5), methyl 2-hydroxyphenylacetate (6), and methyl 4-hydroxyphenylacetate (7). The structure of each was determined by analyses of high-resolution mass spectra and high-field NMR data. Asperic acid (4) was found to inhibit growth of the murine lymphocytic leukemia P388 (ED₅₀ 0.18 Hg/mL) and a panel of human cancer cell lines (GI₅₀ 1.7-2.0 μg/mL; pancreas, breast, CNS, lung, colon, and prostate), while aspergillol A (2) showed moderate inhibition against the breast adenocarcinoma MCF-7 (GI₅₀ 7.2 μg/mL).