THE STRUCTURE OF GLYEURYSAPONIN

A species of the genus Glycyrrhiza, G. eurycarpa P. C. Li recently reported as a new species growing in Gansu Province and Xinjiang Autonomous Region has rarely been studied before on its chemical constituents. This paper reports the isolation and chemical elucidation of two triterpene glucosides named glyeurysaponin (K-4) and uralsaponin B (K-3)from this species collected in Jinta County, Gansu Province. Their chemical structures were elucidated by means of chemical and spectrometric analysis (UV, IR, MS, ¹HNMR and ¹³CNMR)and were first reported to be present in this plant. Glyeurysaponin (K-4), C₄₂H₆₂O₁₆ was obtained as white crystals, mp 288℃ (d),α_D¹⁸+22.5°(c 0.62, 60% MeOH ). Its structure was found to be 3β- hydroxy- 11-oxo- olean-12-en-30-oic acid-3-O -β- D-glucuronopyranosyl-(1→4 )-β- D -glucuronopyranoside. Glyeurysaponin is a new triterpenoid saponin. The known saponin was identified to be 3β- hydroxy- 11-oxo- olean- 12- en-30- oic acid-3-O -β- D-glucuronopyranosyl-(1→ 3 ) -β- D- glucuronopyranoside, uralsaponin B.