Naphtho-γ-pyrones from Endophyte Aspergillus niger Occurring in the Liverwort Heteroscyphus tener (STEPH.) SCHIFFN.

Bioactivity-guided fractionation of the cytotoxic extract of Aspergillus niger, an endophytic fungus from the Chinese liverwort Heteroscyphus tener (Steph.) Schiffn., afforded five new naphtho--pyrones, rubrofusarin-6-O--D-ribofuranoside (1), (R)-10-(3-succinimidyl)-TMC-256A1 (2), asperpyrone E (3), isoaurasperone A (4), and isoaurasperone F (5), as well as four known ones, dianhydroaurasperone C (6), aurasperone D (7), asperpyrone D (8), and asperpyrone A (9), together with a cytotoxic cyclic pentapeptide, malformin A(1) (10). Their structures were determined by extensive spectroscopic analysis. The absolute configurations of dimeric naphtho--pyrones 3-9 were also determined by analysis of their respective CD spectra.