Indole-benzodiazepine-2,5-dione derivatives from a soil fungus Aspergillus sp. PSU-RSPG185

Six new indole-benzodiazepine-2,5-dione derivatives, asperdiazapinones A–F (1–6), together with three known prenylated indole alkaloids were isolated from the mycelial extract of the soil fungus Aspergillus sp. PSU-RSPG185. Their structures were established by spectroscopic evidence. For compounds 2 and 5, the structures were confirmed by single-crystal X-ray diffraction crystallography. Asperdiazapine B (2) displayed weak antimalarial and noncytotoxic activities.