A new aglycone derivative from the saprophytic fungus Tubeufia rubra

A new aglycone derivative (1) and five known compounds (2-6) have been isolated from a saprophytic fungus Tubeufia rubra for the first time. Their structures and absolute configurations were determined by nuclear magnetic resonance, high resolution mass spectrometry data and electronic circular dichroism. The bioactivities of all compounds were evaluated by cell analysis. Compound 5 showed significant toxicity to human cancer A549 cells, and the IC₅₀ value was 32. 89 μg/mL. Compound 6 could reverse the multidrug resistance of A549/DDP cells, and the reversal value was 2.92. With the extension of the action time, the IC50 value of compound 6 decreased from 424.72 μg/mL at 24 h to 9.45 μg/mL at 72 h.