C-21 steroidal glycosides from Dregea sinensis.

Two new C-21 steroidal glycosides, dregeosides D (1) and E (2), were isolated from the roots of Dregea sinensis. The structures of the isolated compounds were elucidated on the basis of 1D and 2D NMR spectra and HR-ESI-MS analysis. Finally, the inhibited effects of the isolated compounds on interleukin 2 receptor were evaluated by enzyme-linked immunosorbent assay.