Novel Polyoxygenated Spirostanol Glycosides from the Rhizomes of Helleborus orientalis

The two new polyoxygenated spirostanol bisdesmosides 1 and 2 and the new trisdesmoside 3, named hellebosaponin A (1), B (2), and C (3), respectively, were isolated from the MeOH extract of the rhizomes of Helleborus orientalis. The structures of the new compounds were elucidated as (1β,3β,23S,24S)-21-(acetyloxy)-24-[(β-D-fucopyranosyl)oxy]-3,23-dihydroxyspirosta-5,25(27)-dien-1-yl O-β-D-apiofuranosyl-(13)-O-(4-O-acetyl-α-L-rhamnopyranosyl)-(12)-O-[β-D-xylopyranosyl-(13)]-α-L-arabinopyranoside (1), (1β,3β,23S,24S)- 21-(acetyloxy)-24-{[O-β-D-glucopyranosyl-(14)-β-D-fucopyranosyl]oxy}-3,23-dihydroxyspirosta-5,25(27)-dien-1-yl O-β-D-apiofuranosyl-(13)-O-(4-O-acetyl-α-L-rhamnopyranosyl)-(12)-O-[β-D-xylopyranosyl-(13)]- α-L-arabinopyranoside (2), and (1β,3β,23S,24S)-24-[(β-D-fucopyranosyl)oxy]-21-{[O-β-D-glucopyranosyl-(12)-β-D-galactopyranosyl]oxy}-3,23-dihydroxyspirosta-5,25(27)-dien-1-yl O-β-D-apiofuranosyl-(13)-O-(4-O-acetyl-α-L-rhamnopyranosyl)-(12)-O-[β-D-xylopyranosyl-(13)]-α-L-arabinopyranoside (3), respectively, on the basis of detailed spectroscopic studies and chemical evidence.