Chemical shift assignments of two oleanane triterpenes from Euonymus hederaceus

INTRODUCTION Euonymus hederaceus champ.ex Benth (Celas-traceae) has been used as a traditional medical plant (Chang et al., 1996). Two compounds, 12-oleanene-3,11-dione and 28-hydroxyolean-12-ene-3,11-dione (Fig.1) were isolated by its phytochemical investiga-tion. The complete 1H and 13C chemical shift as-signments of 12-oleanene-3,11-dione are described here for the first time with 1D and 2D NMR, cor-recting some data in Yuan et al.(1994). The 13C as-signments of 28-hydroxyolean-1…