Six New Steroidal Saponins from Helleborus thibetanus

Six steroidal saponins, including five spirostanol glycosides, 1–5, and one furostanol glycoside 1‐sulfonate, 6, previously unknown in nature, together with three known compounds, 7–9, were isolated from dried roots and rhizomes of Helleborus thibetanus. Their structures were elucidated by extensive 1D‐ and 2D‐NMR experiments, along with IR and HR‐ESI‐MS data, as well as the results of acid hydrolysis. Compounds 1–5 possessed a C(25)C(27) bond and were glycosylated at HOC(1), which was unusual in steroidal saponins.