Abstract: To study the chemical constituents, the ethanol extract of dried stem of Akebia quinata(Thunb.) Decne. was seperated by dichloromethane, n-butanol in sequence. The n-butanol extract was further isolated by D101 macroporous resin and silica gel column chromatography. A new triterpene with two known triterpenes were isolated, their structures were identified as 3α,24-dihydroxy-30-norolean-12,20(29)-dien-28-oic acid (Ⅰ), 3α,24,29-trihydroxyolean-12-en-28-oic acid (Ⅱ), 2α,3β,23-trihydroxyolean-12-en-28-oic acid (Ⅲ). The new compound Ⅱ was nominated as quinatic stem acid. The structures were identified and elucidated by physicochemical properties and spectral analysis.

Key words: Akebia, Akebia quinata(Thunb.)Decne., Triterpene, Quinatic stem acid