[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 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 degrees C (d), [alpha]18D + 22.5 degrees (c 0.62,60%MeOH). Its structure was found to be be 3 beta-hydroxy-11-oxo-olean-12-en-30-oic acid-3-O-beta-D-glucuronopyranosyl-(1----4)-beta-D-glucuronopyr anoside. Glyeurysaponin is a new triterpenoid saponin. The known saponin was identified to be 3 beta-hydroxy-11-oxo-olean-12-en-30-oic acid-3-O-beta-D-glucuronopyranosyl-(1----3)-beta-D-glucuronopyr anoside, uralsaponin B.