Cis-aconitic anhydride ethyl ester and phenolic compounds from the seeds of Alisma orientale.

From the seeds of Alisma orientale, cis-aconitic anhydride ethyl ester and cis-2,4,5-trihydroxycinnamic acid were isolated, together with nine known phenolic compounds and a megastigmane sesquiterpene. All compounds are reported for the first time from Alisma species.