Lithocarpins E—G, Potent <scp>Anti‐Tumor Tenellone‐Macrolides</scp> from the <scp>Deep‐Sea</scp> Fungus <i>Phomopsis lithocarpus</i><scp>FS508</scp>
Jianlin Xu, Yuchan Chen, Zhaoming Liu, Saini Li, Yong Wang, Yuhong Ren, Hongxin Liu, Weimin Zhang
Abstract
Main observation and conclusion Lithocarpins E—G, featuring a rare naturally‐occurring highly oxygenated tenellone‐macrolide skeleton, were isolated from the culture extract of a marine‐derived fungus Phomopsis lithocarpus FS508. Their structures were fully elucidated by NMR and MS spectroscopic analyses and electronic circular dichroism calculations. Compounds 1 — 3 were evaluated for their in vitro cytotoxicities against HepG2, MCF‐7, SF‐268, as well as A549 cell lines, among which, compound 1 exhibited inhibitory activity against HepG2 cells with an IC 50 value of 6.3 μmol/L. The further mechanistic investigation demonstrated that lithocarpin E could cause the apoptosis of HepG2 cells through activation of p‐ERK, Bax, and caspase‐3 gene expressions.