Ardeemins and citrinin dimer derivatives from Aspergillus terreus harbored in Pinellia ternate

Abstract One new alkaloid, 15b-β-hydroxy-16α-hydroxy-5-N-acetylardeemin (1), and one new dimeric derivative of citrinin, penicitrinol Q (5), together with three known alkaloids (2–4) and two citrinin dimers (6–7), were isolated from the solid culture of an endophytic Aspergillus terreus resided in Pinellia ternata. Their structures were established by detailed spectroscopic analysis, and the absolute configurations were determined by single crystal X‑ray diffraction and the comparison of ECD spectra. Penicitrinol Q (5) exhibited inhibitory effects against Staphylococcus aureus and Bacillus subtilis with MIC50 values of 4.3 and 6.2 μg/mL, respectively. When using a concentration of 30 μM, compound 2 showed 2.1-fold enhancement of doxorubicin susceptibility in treating doxorubicin-resistant human breast cancer cell line.