Two New Cytotoxic Steroidal Alkaloids from Sarcococca Hookeriana

Two new steroidal alkaloids, named hookerianine A (1) and hookerianine B (2) were isolated from the stems and roots of Sarcococca hookeriana Baill., along with two known compounds, sarcorucinine G (3) and epipachysamine D (4). On the basis of spectroscopic methods and by comparison with literature data, their structures were determined. As well as X-ray crystallography was performed to confirm compound 4. To identify novel antitumor inhibitors, all compounds were performed a CCK-8 assay against five human cancer cell lines SW480, SMMC-7721, PC3, MCF-7 and K562 in vitro. Compound 2 exhibited moderate cytotoxic activities to all cell lines with IC₅₀ values in the range of 5.97⁻19.44 μM. Compound 3 was the most effective one against SW480 and K562 cell lines with IC₅₀ values of 5.77 and 6.29 μM, respectively.