Antibacterial and NF-κB Inhibitory Lumazine Peptides, Aspochalasin, γ‑Butyrolactone Derivatives, and Cyclic Peptides from a Hawaiian Aspergillus flavipes

Five new lumazine peptides (1–5), a new aspochalasin derivative (6), and a new γ-butyrolactone derivative (7), together with seven known compounds (8–14), were isolated from a Hawaiian fungal strain, Aspergillus flavipes FS888. Compound 1 is an uncommon natural product containing an isocyano group. The structures of the new compounds 1–7 were elucidated by NMR spectroscopy, HRESIMS, chemical derivatization, and ECD analysis. Compounds 12–14 showed significant antibacterial activity against S. aureus when in combination with disulfiram. Additionally, compounds 9 and 13 showed NF-κB inhibitory activity with IC50 values of 3.1 ± 1.0 and 10.3 ± 2.0 μM, respectively.