Structural studies of triterpenoid saponins with new acyl components from Quillaja saponaria Molina

Eight new triterpenoid saponins were isolated from a bark extract of Quillaja saponaria Molina by silica and reverse phase chromatography. The saponins were characterized by spectroscopic data and chemical methods as phytolaccagenic acid, 22β-hydroxy-quillaic acid, and echinocystic acid substituted with different oligosaccharides at C-3 and C-28. The O-4 of the fucosyl residue in the 28- O-oligosaccharide was substituted with either acetyl, ( S)-2-methylbutanoyl, or (3 S,4 S)-3-hydroxy-4-methylhexanoyl groups.