A navel beta -glucuronidase inhibiting triterpene (1) has been isolated fro
m the chloroform fraction of Paeonia emodi. Its structure has been establis
hed as 1 beta ,3 beta ,5 alpha ,23,24-pentahydroxy-30-norolean-12,20(29)-di
en-28-oic acid on the basis of spectroscopic analysis, including high resol
ution mass spectroscopy, one and two-dimensional NMR techniques. Oleanolic
acid, betulinic acid, ethyl gallate, methyl grevillate and 1,5-dihydroxy-3-
methyl-anthraquinone are also reported for the first time from Paeonia emod
i.