Synthesis and cytotoxic activity of the N-acetylglucosamine-bearing triterpenoid saponins

Fourteen ursolic acid and oleanolic acid saponins with N-acetyl-β-d-glucosamine, and (1→4)-linked and (1→6)-linked N-acetyl-β-d-glucosamine oligosaccharide residues were synthesized in a convergent manner. The structures of all compounds were confirmed by 1H NMR and 13C NMR spectroscopy and by mass spectrometry, and their cytotoxic activities were assayed in three cancer cell lines. Only oleanolic acid-3-yl β-d-GluNAc showed significant cytotoxicity against HL-60 and BGC-823.

Graphical abstractFourteen ursolic acid and oleanolic acid saponins, where R = GlcNAc or (1→4)-linked and (1→6)-linked GlcNAc oligosaccharide residues were synthesized in a convergent manner and evaluated for their cytotoxic activity in three cancer cell lines. R1 and R2 = H or CH3.Figure optionsDownload full-size imageDownload as PowerPoint slide