Naphpyrones A–H,\nAntibacterial Aromatic Polyketides\nIsolated from the Streptomyces coelicolor A3(2)/<i>spi1</i> Δ<i>spi</i>H3

Staphylococcus aureus,\na common\nfoodborne pathogen, has a close association with agriculture and food.\nWith the rapid emergence and widespread dissemination of antimicrobial\nresistance, efforts have been directed toward developing and studying\nnew antimicrobial compounds to inhibit the growth of S. aureus and other foodborne pathogens, thereby\npreventing contamination and ensuring food safety. Herein, we reported\neight new aromatic polyketides, naphpyrones A–H (<b>1</b>–<b>8</b>), from the heterologous expression strain Streptomyces coelicolor A3(2)/<i>spi1</i> Δ<i>spi</i>H3. Their structures and absolute configurations\nwere elucidated by extensive NMR, MS, theoretical NMR calculations,\nDP4+ probability analysis, Mosher’s method, and ECD analyses.\nNotably, naphpyrone A (<b>1</b>) featured an unprecedented 6/6/6/6/5\nneocyclic skeleton. Bioactivity evaluation revealed that compounds <b>1</b> and <b>2</b> exhibited antibacterial activity against S. aureus, with MIC values of 1 μg/mL and 4\nμg/mL, respectively. These findings highlight the potential\nfor screening and developing therapeutic agents from actinomycetes-derived aromatic polyketides against\nfood pathogens.