Post-modification of the isoprenoid ring in pyripyropenes critically modulates their structural diversity and bioactivity. Here, we report the engineered biosynthesis of novel pyripyropene derivatives via reconstruction of the pyripyropene A gene cluster and its heterologous expression in Aspergillus nidulans. Five previously unreported compounds—1-keto-pyripyropene E (1), 13-hydroxy-1-keto-pyripyropene E (2), deacetyl-pyripyropene G (3), 11-deoxo-deacetyl-pyripyropene A (4), and 1-keto-11-deoxo-deacetyl-pyripyropene A (5)—were isolated from the engineered strain. Their structures were unequivocally characterised by MS and NMR spectroscopy, with compounds 1, 2, and 5 representing the first examples of 1-ketone pyripyropenes. Significantly, these 1-ketone derivatives exhibited significantly enhanced insecticidal activity compared to their 1-hydroxy analogues, demonstrating their potential as next-generation insecticide leads.

Four dimeric diketopiperazine stereoisomers (1–4) including two new ones (1–2) had been isolated from the culture broth of one marine-derived fungus Aspergillus sp. Z3, which was found in the gut of a marine isopod Ligia exotica. The planner structures and absolute configurations of the new compounds were determined by combination of NMR, HRESIMS, electronic circular dichroism calculation, Marfey’s method as well as single-crystal X-ray diffraction. Their cytotoxicity against the prostate cancer PC3 cell line was assayed by the MTT method.