A new pentacyclic triterpenoid glucoside from Prunus serrulata var. spontanea.

A new triterpenoid, 2alpha,3alpha,24-trihydroxyurs-12-en-28-oic acid-28-O-beta-D-glucopyranosyl ester (4) along with four known triterpenoids, ursolic acid (1), 2alpha-hydroxyursolic acid (2), 2alpha,3alpha,24-trihydroxyurs-12-en-28-oic acid (3), and 2alpha,3alpha,19alpha,24-tetrahydroxyurs-12-en-28-oic acid-28-O-beta-D-glucopyranosyl ester (5), were isolated from the leaves of Prunus serrulata var. spontanea (Rosaceae). Compounds 3-5 showed ONOO(-) scavenging activity, whereas compounds 1 and 2 were virtually inactive.