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Eutypellenoids A⁻C, New Pimarane Diterpenes from the Arctic Fungus Eutypella sp. D-1
Hao-Bing Yu1,2, Xiao-Li Wang3, Wei-Heng Xu4
1Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, and Marine Biopharmaceutical Institute, Second Military Medical University, Shanghai 200433, China. yuhaobing1986@126.com.
Abstract:
Three new pimarane diterpenes, eutypellenoids A⁻C (1⁻3), together with a known compound, eutypenoid C (4), were isolated from the culture extract of Eutypella sp. D-1 derived from the Arctic region. Compounds 1⁻3 possessed an uncommon tetrahydrofuran-fused pimarane diterpene skeleton. The structures of all compounds were determined by detailed spectroscopic analysis, electronic circular dichroism (ECD) analysis, as well as a comparison with the literature data. Antibacterial, antifungal, and cytotoxic activities of these compounds were evaluated. Compound 2 displayed antibacterial activity against Staphylococcus aureus and Escherichia coli with MIC values of 8 and 8 μg/mL, respectively. Additionally, compound 2 showed antifungal activity against Candidaparapsilosis, Candida albicans, Candida glabrata, and Candida tropicalis with MIC values of 8, 8, 16, and 32 μg/mL, respectively. Furthermore, compound 2 exhibited moderate cytotoxic activity against HCT-116 cell line with IC50 value of 3.7 μM.
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