New triterpenoids from Leonurus japonicus (Lamiaceae)

Three new triterpenoids (1, 4, and 5), together with 17 known analogues, were isolated from the ethyl acetate soluble portion of the EtOH extract of Leonurus japonicus Houtt. Their structures were determined by spectroscopic analysis. All known triterpenoids were isolated from the genus Leonurus for the first time. Among them, triterpenoids 2–3, 9–12, and 16–20 were first isolated from the family Lamiaceae. Furthermore, the cycloartane, taraxastane, ursane, lupane, euphane, and dammarane types are reported here for the first time from the genus Leonurus.