Triterpene Glucosides from the Leaves of Aralia elata and Their Cytotoxic Activities

Three new triterpene glucosides, named congmuyenosides C–E (1–3, resp.), along with four known ones, were isolated from an EtOH extract of Aralia elata (Miq.) Seem. leaves. The structures of the new compounds were identified as 3‐O‐{β‐D‐glucopyranosyl‐(1→3)‐β‐D‐glucopyranosyl‐(1→3)‐[β‐D‐glucopyranosyl‐(1→2)]‐β‐D‐glucopyranosyl}caulophyllogenin (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‐glucopyranosyl ester (2), 3‐O‐{β‐D‐glucopyranosyl‐(1→3)‐β‐D‐glucopyranosyl‐(1→3)‐[β‐D‐glucopyranosyl‐(1→2)]‐β‐D‐glucopyranosyl}echinocystic acid 28‐O‐β‐D‐glucopyranosyl ester (3) on the basis of spectral analyses, including MS, 1H‐NMR, 13C‐NMR, DEPT, HSQC, HMBC, NOESY, and HSQC‐TOCSY experiments. All isolates obtained were evaluated for their cytotoxic activities against three human tumor cell lines (HepG2, SKOV3, and A549). Compound 3 showed significant cytotoxicity against A549 cell line (IC50 9.9±1.5 μM).