The Discovery of Acremochlorins O-R from an sp. through Integrated Genomic and Molecular Networking.

The fermentation of a soil-derived fungus sp. led to the isolation of thirteen ascochlorin congeners through integrated genomic and Global Natural Product Social (GNPS) molecular networking. Among the isolated compounds, we identified two unusual bicyclic types, acremochlorins O () and P (), as well as two linear types, acremochlorin Q () and R (). Compounds and contain an unusual benzopyran moiety and are diastereoisomers of each other, the first reported for the ascochlorins. Additionally, we elucidated the structure of , a 4-chloro-5-methylbenzene-1,3-diol with a linear farnesyl side chain, and confirmed the presence of eight known ascochlorin analogs (-). The structures were determined by the detailed interpretation of 1D and 2D NMR spectroscopy, MS, and ECD calculations. Compounds and showed potent antibacterial activity against and , with MIC values ranging from 2 to 16 μg/mL.