Three new diphenyl ethers from the lichen Parmotrema praesorediosum (Nyl.) Hale (Parmeliaceae)

Abstract

Three new diphenyl ethers, named praesorethers E, F and G (1, 2 and 3), were isolated from the lichen Parmotrema praesorediosum. Their chemical structures were elucidated on the basis of extensively spectroscopic analysis including HR-ESI-MS and NMR as well as comparison with previously published data. These compounds were evaluated for the cytotoxicity against three human cancer cell lines (HeLa, NCI-H460 and MCF-7) using SRB assay. As results, 1 and 2 exhibited weak cytotoxic activity against three tested cancer cell lines with the inhibitive percentage of 64–79.9% at the concentration of 100 μg/mL while 3 was inactive.

Graphical Abstract

Keywords:

• Parmotrema praesorediosum
• Parmeliaceae
• praesorether
• diphenyl ether
• cytotoxicity

Acknowledgements

The authors would like to thank Dr. Thi-Phi-Giao Vo, Department of Biology, University of Science, University of Science, National University HCM City, Vietnam for the authentification of the scientific name for the studied species.

Disclosure statement

No potential conflict of interest was reported by the authors.