Pleosporalins H and I, two new heptaketides from the endophytic fungus Pleosporales sp. F46 by using OSMAC strategy

Abstract

Two new heptaketides, pleosporalins H and I (1 and 2), as well as seven biosynthetically related known polyketides (3–9) were isolated from the endophytic fungus, Pleosporales sp. F46 by employing the one strain-many compounds (OSMAC) approach. The planar, relative and absolute structures of these compounds were identified by extensive spectroscopic analysis including HRMS, NMR, optical rotations and ECD calculations. The cytotoxic efficiencies of all isolated compounds 1–9 were evaluated against four cancer cell lines A549, CT-26, MCF-7 and MDA-MB-231.

Graphical Abstract

Keywords:

• Endophytic fungus
• Pleosporales sp. F46
• natural products
• heptaketides
• cytotoxic activity

Acknowledgements

We gratefully acknowledge Dr. Wen-Xuan Wang (School of Pharmaceutical Sciences, South-Central University of Nationalities) for the quantum chemistry analysis and valuable discussions.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by Scientific Research Foundation of Qingdao University and National Natural Science Foundation of China (no. 81903494 and 41706077).