A new quinolinone from freshwater <b> lake-derived</b> fungus <i>Myrothecium verrucaria</i>

<p>One new quinolinone, 7-hydroxy-3-methoxyviridicatin (<b>1</b>), along with eight known compounds (<b>2</b>–<b>9</b>) was isolated from the fungus <i>Myrothecium verrucaria</i>, which was collected from lake water of Chenghai, Yunnan Province, China<i>.</i> Their structures were elucidated by detailed analysis of spectroscopic data and comparison with related known compounds. Compounds <b>1</b> and <b>2</b> exhibited weak antibacterial activity. To the best of our knowledge, this is the first report on quinolinones (<b>1</b>–<b>4</b>) as the secondary metabolites of <i>M. verrucaria</i><i>.</i></p>