Xylariaopyrones E-I, five new α-pyrone derivatives from the endophytic fungus Xylarialessp. (HM-1)

作者：Yang, Wen-Wen; Lu, Li-Wen; Zhang, Xue-Qing^*; Bao, Shang-Song; Cao, Fei; Guo, Zhi-Yong^*; Deng, Zhang-Shuang; Proksch, Peter

来源：NATURAL PRODUCT RESEARCH, 2022, 36(9): 2230-2238.

DOI：10.1080/14786419.2020.1826480

• alpha-Pyrones
• Xylariales sp.
• antimicrobial activity
• monoamine oxidase B
• brine shrimp mortality

Five new alpha-pyrones, xylariaopyrones E-I (1-5), along with three known analogues (6-8) were isolated from the cultivation broth of the endophytic fungus Xylarialessp. (HM-1). The structures of the new compounds including their absolute configurations were elucidated by comprehensive spectroscopic methods and quantum ECD calculations. Xylariaopyrone E (1) is the first example of alpha-pyrone derivative with a novel [3, 2, 0] bridge ring system via a ketal function group in the side chain. In bioactivity assays, xylariaopyrones E-G (1-3) showed moderate inhibiting activities against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa with MIC values from 25.4 to 64.5 mu g/mL, wherer as xylariaopyrone G (3) exhibited significant inhibition of monoamine oxidase B with an IC50 value of 15.6 mu mol/L. Xylariaopyrone H (4) and the known compound 7 showed moderate toxicity against brine shrimp larvae with inhibition rates of 42.8% and 44.5%, respectively. @@@ [GRAPHICS] @@@ .