Isolation and characterization of 2-pyridone alkaloids and alloxazines from Beauveria bassiana

Two novel compounds bearing heterocyclic nitrogen, 2-pyridone alkaloid (1) and alloxazine derivative (2), along with the known pretenellin B (3), pyridovericin (4) and lumichrome (5) were isolated from a culture of the entomopathogenic fungal strain Beauveria bassiana. The chemical structures of 2-pyridone alkaloid and alloxazine derivative were established on the basis of the interpretation of spectroscopic data. The isolated compounds were evaluated in a panel of five cancer cell lines and pyridovericin exhibited cytotoxicity (IC50, M) against cancer cell lines: HL-60 (25.9 +/- 0.3), HCT8 (34.6 +/- 3.6), MDA-MB435 (34.8 +/- 3.8) and SF295 (31.1 +/- 0.6). Considering that other pyridone compounds display good cytotoxic activity, it would be suggested to obtain new semi synthetic derivatives of pyridovericin, for the development of new cytotoxic chemical entities. [GRAPHICS] .