New sesquiterpenoid derivatives from Solanum lyratum and their cytotoxicities

Abstract

Three new sesquiterpenoid isopropylidene derivatives, named solajiangxins H and I (1 and 2) and 7-hydroxylsolajiangxin I (3), were isolated from the whole plant of Solanum lyratum. Their structures were elucidated on the basis of integrated spectroscopic techniques, mainly HR-FAB-MS, 1D NMR, and 2D NMR (¹H–¹H COSY, HMQC, HMBC, and NOESY). In vitro, compounds 1–3 were found to show significant cytotoxicity against three cancer cells (P-388, HONE-1, and HT-29), and gave IC₅₀ values in the range of 3.2–7.7 μM.

Keywords::

• Solanum lyratum
• sesquiterpenoid isopropylidene derivatives
• solajiangxins H and I
• 7-hydroxylsolajiangxin I
• cytotoxic activity

Acknowledgments

This study was financially supported by the Natural Science Foundation of Shandong Province (No. ZR2009CZ004). The authors are grateful to Ms Wen-Yan Wang and Li Shen (School of Pharmaceutical Science, Yantai University) for the measurements of FAB-MS, HR-FAB-MS, UV, IR, and NMR spectra, respectively. The authors also gratefully acknowledge Mr Hong-Bo Wang (School of Pharmaceutical Science, Yantai University) for the bioactivity screenings.