A new sesquiterpenes from Pteris wallichiana and its anticancer activity

The methanol extract of Pteris wallichiana was separated and purified by MCI gel, sephadex LH 20, flash C18 and silica gel column chromatography combined with semi-pre HPLC. The chemical structures of the isolated compounds were identified by MS, IR, NMR, etc. Five sesquiterpene compounds were isolated from Pteris wallichiana and identified as 6,7-tetrahydrofuran-(2S, 3S)-pterosin C-3-O-β-D-(6′-acetyl)-Glu (1), (2S, 3S)-pterosin C-3-O-β-D-Glu (2), (2S)-pterosin A (3) and (2S)-13-hydroxyl-pterosin A (4), (2R, 3S)-2-hydroxyl-pterosin C (5). Compound 1 is a new sesquiterpene, compounds 3-5 were isolated for the first time. In vitro bioactivity assay showed that compound 1 was able to inhibit the proliferation of 4T1 and EMT6 cells, and possessed significant anti-triple-negative breast cancer bioactivity.