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The fermentation of a soil-derived fungus <i>Acremonium</i> 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 (<b>1</b>) and P (<b>2</b>), as well as two linear types, acremochlorin Q (<b>3</b>) and R (<b>4</b>). Compounds <b>1</b> and <b>2</b> contain an unusual benzopyran moiety and are diastereoisomers of each other, the first reported for the ascochlorins. Additionally, we elucidated the structure of <b>5</b>, a 4-chloro-5-methylbenzene-1,3-diol with a linear farnesyl side chain, and confirmed the presence of eight known ascochlorin analogs (<b>6</b>–<b>13</b>). The structures were determined by the detailed interpretation of 1D and 2D NMR spectroscopy, MS, and ECD calculations. Compounds <b>3</b> and <b>9</b> showed potent antibacterial activity against <i>Staphylococcus aureus</i> and <i>Bacillus cereus</i>, with MIC values ranging from 2 to 16 μg/mL.