Cytotoxic triterpene saponins from the leaves of Aralia elata

Phytochemical investigation of the leaves of Aralia elata has led to the isolation of four new compounds, 3-O-β-d-glucopyranosyl (1 → 3)-β-d-glucopyranosyl (1 → 3)-β-d-glucopyranosyl oleanolic acid (1), 3-O-[β-d-glucopyranosyl (1 → 3)-β-d-glucopyranosyl (1 → 3)]-[β-d-glucopyranosyl (1 → 2)]-β-d-glucopyranosyl hederagenin 28-O-β-d-glucopyranoside (2), 3-O-{[β-d-glucopyranosyl (1 → 2)]-[β-d-glucopyranosyl (1 → 3)-β-d-glucopyranosyl (1 → 3)]-β-d-glucopyranosyl} oleanolic acid 28-O-β-d-glucopyranosyl ester (3) and 3-O-[β-d-glucopyranosyl (1 → 2)]-[β-d-glucopyranosyl (1 → 3)]-β-d-glucopyranosyl caulophyllogenin (4) and two known compounds, 3-O-[β-d-glucopyranosyl (1 → 3)-α-l-arabinopyranosyl]-echinocystic acid (5) and 3-O-α-l-arabinopyranosyl echinocystic acid (6). The structural determination was accomplished with spectroscopic analysis, in particular 13C-NMR, 2D-NMR and HR-ESI-MS techniques. Compounds 1–6 were tested for their inhibition of the growth of HL60, A549 and DU145 cancer cells. Compound 1 showed significant cytotoxic activity against HL60 and A549 cancer cells with IC50 values of 6.99 μM and 7.93 μM respectively. In addition, compounds 5 and 6 showed significant cytotoxic activity against HL60 cancer cells with IC50 values of 5.75 μM and 7.51 μM, respectively.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (230 K)Download as PowerPoint slide