A New Rumenic Acid Derivative from the Roots of Cudrania tricuspidata

A new rumenic acid derivative, threo-9,10-O-isopropylidene-13-hydroxy-(11E)-octadecenoic acid (1), and two known compounds, steppogenin (2) and oxyresveratrol (3), were isolated from the roots of Cudrania tricuspidata. The structure of the new compound was established by spectroscopic methods. All the compounds were evaluated for their cytotoxicity against three human tumor cell lines (HepG2, HCT-116, and SGC-7901). Unfortunately, none of them exhibited significant cytotoxicity at a concentration of 100 μM.