Chem. Pharm. Bull. 55(2) 273—279 (2007)

Tacca chantrieri ANDRÉ is a perennial plant belonging to the family Taccaceae and is indigenous to southeast region of the People’s Republic of China. A decoction prepared from the rhizomes of T. chantrieri has long been used in traditional Chinese medicine for the treatment of gastric ulcer, enteritis, and hepatitis. Our previous chemical studies on the rhizomes of T. chantrieri led to the isolation of diarylheptanoids, diarylheptanoid glucosides, and steroidal glycosides such as spirostanol, furostanol, pseudofurostanol, pregnane, and withanolide glycosides, some of which showed cytotoxic activities against cultured tumor cells. Further phytochemical analysis of T. chantrieri rhizomes, with particular inference to the glycoside constituents, has resulted in the isolation of five new glycosides, which are classified into two bisdesmosidic pseudofurostanol glycosides (1, 2), two new ergostanol glycosides (3, 4), and a new phenolic glycoside (5). This paper reports the structural determination of the new glycosides, which was carried out on the basis of extensive spectroscopic analysis, including that of two-dimensional (2D) NMR data, as well as hydrolytic cleavage followed by spectroscopic and chromatographic analyses. The rhizomes of Tacca chantrieri (dry weight of 7.3 kg) were extracted with hot MeOH twice. After removal of the solvent, the extract was passed through a porous-polymer polystyrene resin (Diaion HP-20) column, successively eluted with MeOH–H2O gradients, EtOH, and EtOAc. The MeOH eluate portion was subjected to silica gel and octadecylsilanized (ODS) silica gel column chromatography to afford compounds 1—5. Compound 1 was isolated as an amorphous solid. The high-resolution electrospray-ionization time of flight mass spectrum (HR-ESI-TOF-MS) of 1 exhibited an accurate [M Na] ion at m/z 1231.5692, allowing the molecular formula of 1 to be assigned as C57H92O27, which was confirmed by analysis of the C-NMR sepctrum combined with distortionless enhancement by polarization transfer (DEPT) specNew Glycosides from the Rhizomes of Tacca chantrieri