Three new saponins from the leaves of Ilex hylonoma

Abstract

Three new triterpenoid saponins, hylonosides III–V (1–3) have been isolated, along with three known oleanolic acid saponins (4–6), from the methanol extract of leaves of Ilex hylonoma. The structures were elucidated using a combination of homo- and hetero-nuclear 2D NMR techniques (COSY, TOCSY, NOESY, HMQC and HMBC) and negative FAB-MS. The new compounds were characterized as 3-O-β-D-glucopyranosyl-(1→4)-β-D-glucuronopyranosyl siaresinolic acid-28-O-β-D-glucopyranosyl ester (1), 3-O-β-D-glucopyranosyl-(1→4)-β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl siaresinolic acid-28-O-β-D-glucopyranosyl ester (2), 3-O-β-D-glucopyranosyl-(1→4)-β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl oleanolic acid-28-O-β-D-glucopyranosyl ester (3).

Keywords:

• Aquifoliaceae
• Triterpenoid saponin

Acknowledgements

This work was supported by the Natural Science Fund (2002) of Huaqiao University. We thank the staff of the analytical group of Kunming Institute of Botany, Chinese Academy of Sciences for measuring spectra.