Five new cucurbitane triterpenoids with cytotoxic activity from Hemsleya jinfushanensis

Abstract Five new cucurbitane triterpenoids (hemslepenside B–E ( 1 – 3 and 5 )), one new cucurbitane (16,25- O -diacetyl-cucurbitane F ( 4 )), and six analogues ( 6 – 11 ) were isolated from the roots of Hemsleya jinfushanensis . The structures of 1 – 5 were elucidated using infrared absorption spectroscopy (IR), high resolution electrospray ionization mass spectrometry (HR-ESI-MS), and nuclear magnetic resonance spectroscopy (NMR). These five new compounds exhibited cytotoxic effects against lung adenocarcinoma (H460), colon cancer (SW620) and human prostate cancer cells (DU145), and compound 4 showed significant cytotoxic activity, with IC 50 values of 0.046, 0.18 and 0.87 μg/mL. This finding suggests that cucurbitane triterpenoids isolated from H. jinfushanensis should be studied further as potential anti-cancer drugs.