A novel triterpene saponin from the roots of Platycodon grandofiorum

A novel triterpene saponin (1). deapioplatycoside E ［3-O-$\beta$-D-glucopyranosyl-(1$\rightarrow$6)-$\beta$-D-gluco- pyranosyl-(1$\rightarrow$6)-$\beta$-O-glucopyranosYI-2$\beta$.3$\beta$.16$\alpha$.23.24-pentahydroxyolean-12-ene-28-oic acid 28-O-$\beta$-D-xylopyranosyl-(4$\rightarrow$1)-$\alpha$-L -rhamnopyranosyl-(1$\rightarrow$2)-$\alpha$-L -arabinopyranoside］ including seven known saponins (2-7) was isolated from the water extract of the roots of Platycodon grandoflorum (Campanulaceae). The chemical structure of 1 was determined based on the spectral and chemical evidence. (omitted)