Anthraquinone Derivatives Produced by Marine-Derived Fungus Aspergillus versicolor EN-7

The new anthraquinone derivative, 6,8-di-O-methylaverantin (1), together with six known congeners (2-7), were characterized from a culture extract of the marine algous fungus, Aspergillus versicolor EN-7. Their structures were elucidated by spectroscopic methods. A bioassay showed compounds 1, 2 and 5 to have weak inhibition against Escherichia coli, while compound 5 also displayed weak inhibition against Staphylococcus aureus.