New Chromone Compounds from the Marine Derived Fungus Diaporthe Sp. Xw12-1

Four new chromone compounds diaporspchromanones A-C (1–3) and diaporspchromanone H (4), together with three known compounds (5–7) were separated from the marine derived fungus Diaporthe sp. XW12–1. The structures of the new compounds, including their absolute configurations, were elucidated by extensive spectroscopic analysis and the Mosher's ester method. Among them, diaporspchromanones A-C (1–3) possess a 3-substituted-chroman-4-one skeleton, which are rarely found in natural sources. In the bioassays, all compounds were evaluated for their inhibitory activity against lipopolysaccharide-activated nitric oxide (NO) production in RAW264.7 cells. Compounds 2 and 3 showed potent anti-inflammatory effects than the positive control (indomethacin, IC50, 70.33 ± 0.95 μM) (p < 0.05) with IC50 values of 19.06 ± 3.60 and 9.56 ± 0.18 μM, respectively.