Nine new steroidal glycosides from the roots of Cynanchum stauntonii

Nine new steroidal glycosides, named as stauntosides C–K (2, 5, 7–10, 13, 14, and 16), along with seven known compounds (1, 3, 4, 6, 11, 12, and 15) were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses, mainly 1D and 2D NMR, and HRESI-MS, and qualitative chemical methods. Their significance in terms of the chemotaxonomy of C. stauntonii is discussed.

Graphical abstractNine new steroidal glycosides were isolated from the roots of Cynanchum stauntonii. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses and chemical methods.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► More information about the chemical constituents of Cynanchum stauntonii were given. ►·Sixteen compounds were identified, including nine new steroidal glycosides. ►·Two new 14,15-secopregnane-type skeleton aglycones were reported for the first time. ► Several new oligosaccharide chains were found for the first time.