New tirucallane-type triterpenoid saponins from Sapindus mukorossi Gaetn.

Abstract

Two new tirucallane-type triterpenoid saponins, sapimukoside C (1) and sapimukoside D (2), have been isolated from the roots of Sapindus mukorossi Gaetn. Their structures have been determined, on the basis of spectral and chemical analysis, as 3-O-α-L-rhamnopyranosyl-(1→2)-[α-L-arabinopyranosyl-(1→3)]-β-D-glucopyranosyl (21,23R)-epoxyl tirucalla-7,24-diene-(21S)-ethoxyl-3β-ol (1) and 3-O-α-L-rhamnopyranosyl-(1→2)-[α-L-arabinopyranosyl-(1→3)]-β-D-glucopyranosyl (21,23R)-epoxyl tirucall-7, 24-diene-(21S)-methoxyl-3β-ol (2).

Keywords:

• Sapindus mukorossi Gaetn
• Sapindaceae
• Tirucallane-type
• Triterpenoid saponin
• Sapimukoside C
• Sapimukoside D

Acknowledgements

The authors are grateful to Ms Liang Hui-Ling and Wu Yu for measuring the MS spectrum and to Mr Ji Yun-Heng for measuring the optical rotation. This work was financed by the School of Chinese Medicine, the Chinese University of Hong Kong.