Triterpenoids from the Roots and Stems of Rubus alceaefolius

A phytochemical investigation of the roots and stems of Rubus alceaefolius Poir. let to the isolation of two oleanane-type triterpenoids, 2 α ,3 α -dihydroxyolean-11,13(18)-dien-19 β ,28-olide ( 1 ) and 2 α ,3 α -dihydroxyolean-13(18)-en-28-oic acid ( 2 ), and a unique octanordammarane triterpenoid, 3 β -hydroxy- 20,21,22,23,24,25,26,27-octanordammaran-17 β -ol ( 3 ), which the current study is the second report of this type of dammarane triterpenoid. Their structures were elucidated on the basis of spectroscopic evidence, including 1D and 2D NMR and IR analysis, and by comparison with literature data. Compounds 1 and 3 are new compounds, and compound 2 is obtained from nature for the first time.