Paraherquamide J, a new prenylated indole alkaloid from the marine-derived fungus Penicillium janthinellum HK1-6

Abstract

A new prenylated indole alkaloid, named paraherquamide J (1), together with four known compounds (2–5), were isolated from the mangrove rhizosphere soil-derived fungus Penicillium janthinellum HK1-6. The planar structure and relative configuration of 1 were determined by detailed analysis of the spectroscopic data especially the NOESY spectrum. The absolute configuration of 1 was determined by ECD spectra. Compound 2 was first isolated as a natural product and named as paraherquamide K. All isolated metabolites were evaluated for their antibacterial, topoisomerase I (topo I) inhibitory activities and lethality towards brine shrimp Artemia salina.

Graphical Abstract

Keywords:

• marine-derived fungus; Penicillium janthinellum
• prenylated indole alkaloid
• paraherquamide

Acknowledgements

The Testing Center of Yangzhou University is acknowledged for the testing assistance.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (Nos. 81703411, U1606403), major project for the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (No. 17KJA350005), the Scientific and Technological Innovation Project Financially Supported by Qingdao National Laboratory for Marine Science and Technology (No. 2016ASKJ08), and the Taishan Scholars Program, China.