Dibenzofurans from the marine sponge-derived ascomycete Super1F1-09

Abstract

Three dibenzofurans hitherto undescribed from nature and one known butyrolactone were isolated from the extract of the ascomycete Super1F1-09 isolated from the Fijian marine sponge Acanthella cavernosa . The isolated compounds were identified as 3,9-dimethyldibenzo[ b,d ]furan-1,7-diol ( 1 ), 3-(hydroxymethyl)-9-methyldibenzo[ b,d ]furan-1,7-diol ( 2 ), 1,7-dihydroxy-9-methyldibenzo[ b,d ]furan-3-carboxylic acid ( 3 ), and the known butyrolactone I ( 4 ) using different NMR spectroscopic techniques and accurate mass spectrometric analysis. 1 was synthesized together with structurally related dibenzofurans 6 – 8 . 1 and 4 had moderate antibacterial activity toward Mycobacterium marinum and Staphylococcus aureus , whereas 2 and 3 proved inactive. In addition, all compounds had moderate inhibitory properties against epidermal growth factor receptor tyrosine kinase.