Two New Triterpenoid Saponins from the Root of Platycodon grandiflorum

Abstract

Two new triterpenoid saponins, named platycodon A (3-O-β-D-glucopyranosyl-16-O-β-D-glucopyranosyl-2β,3β,16β,21β-tetrahydroxyolean-12-en-28-oic acid) and platycodon B (3-O-β-D-glucopyranosyl-16-O-β-D-xylopyranosyl-2β,3β,16β,21β-tetrahydroxyolean-12-en-28-oic acid) were isolated from the roots of Platycodon grandiflorum. The structures of these compounds were elucidated by means of various spectroscopic analyses. Compounds 1 and 2 were tested in HepG-2, A549 and DU145 human cancer cell lines and showed remarkable cytotoxic activities against HepG-2 and A549 cancer cell lines with IC₅₀ values ranging from 4.9 to 9.4 µM, but they displayed weak cytotoxic activities against DU145 cancer cell line with IC₅₀ values greater than 10 µM.