A New Lupane Glycoside from the Leaves of Acanthopanax koreanum

A new lupane-type saponin, named acankoreoside E (1), was isolated from the methanol extract of the leaves of Acanthopanax koreanum, and its structure was established through chemical and spectroscopic analyses as (20S) 3alpha-hydroxy-30-oxolupan-23,28-dioic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester.