Novel cytotoxic steroidal glycosides from the roots of Liriope muscari.

The present study was designed to investigate the chemical constituents and bioactivities of the roots of Liriope muscari (Decne.) L.H. Bailey. The compounds were isolated through various chromatography techniques, including silica gel, Sephadex LH-20, and semi-preparative HPLC. The structures were elucidated by infrared (IR), mass spectrometric (MS), 1D- and 2D-NMR analyses in comparison with reference data. In addition, the cytotoxicity of these compounds against human breast cancer MDA-MB-435 cells was evaluated by the MTT assay. Two new steroidal glycosides, 25(R, S)-ruscogenin-1-O-[β-D-fucopyranosyl (1→2)]-[β-D-xylopyranosyl(1→3)]β-D-glucopyranoside (Liriopem I, 1) and 25(R, S)- ruscogenin-1-O-[β-D-fucopyranosyl (1→2)]-[β-D-xylopyranosyl(1→4)]-β-D-fucopyranoside (Liriopem II, 2 and two known compounds LM-S6 (3) and DT-13 (4) were isolated and identified. Liriopem I(1), liriopem II(2) and DT-13 (4) showed remarkable cytotoxicity with IC50 values being (0.58 ± 0.08), (0.05 ± 0.10), and (0.15 ± 0.09) μg·mL(-1), respectively. In summary, compounds 1 and 2 identified in the present study exerted cytotoxicity against breast cancer cells, providing a basis for future development of these compounds as novel anticancer agents.