Three new polyketide metabolites from the endophytic fungus Trichoderma protrudens of Hibiscus tiliaceus

Trichodones D-F ( 1 - 3 ), three previously undescribed polyketide compounds featuring conjugated α - β -unsaturated ketone moieties, were isolated from the endophytic fungus Trichoderma protrudens associated with the semi-mangrove plant Hibiscus tiliaceus Linn. The structural elucidation of these compounds was accomplished through the analysis of 1D and 2D NMR spectra, complemented by HR-ESI-MS data. The absolute configurations were determined through comparative analysis of experimental CD and calculated ECD spectra. Additionally, the cytotoxic activities of compounds 1 - 3 against the human breast cancer cell line MCF-7 and the human hepatocellular carcinoma cell line HepG2 were evaluated using the CCK8 assay. Notably, compound 3 exhibited moderate inhibitory activity against HepG2 and MCF-7 cell lines with IC 50 values of 22.7 μM and 55.1 μM, respectively.