Novel Dibenzo[b,e]oxepinones from the Freshwater-Derived Fungus Chaetomium sp. YMF 1.02105

Abstract

Six new dibenzo[b,e]oxepinone metabolites, chaetones A–F (1–6), as well as three known compounds, 1-hydroxy-6-methyl-8-hydroxymethylxanthone (7), citreorosein (8), and emodin (9), were obtained from a freshwater-derived fungal strain Chaetomium sp. YMF 1.02105. Their structures were established on the basis of extensive spectroscopic data analysis and comparison with spectroscopic data reported. Compounds 1–6 are further additions to the small group of dibenzo[b,e]oxepinones represented by arugosins A–H. Compounds 1–7 were tested for their cytotoxic activities against A549, Raji, HepG2, MCF-7, and HL-60 cell lines. The results showed that compound 3 had significant cytotoxicity with IC₅₀ values of 1.2, 1.8, 1.9, 2.3, and 1.6 µg/mL, respectively, against the five cancer cell lines. All compounds showed modest antimicrobial activity against Staphylococcus aureus (ATCC 6538) in standard disk assays.

Key words

dibenzo[b,e]oxepinone - Chaetomium sp. - Chaetomiaceae - chaetones - cytotoxicity - antimicrobial activity

• References

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