Four new biflavonoids from Selaginella uncinata and their anti-anoxic effect

Abstract

The 60% ethanolic extract of Selaginella uncinata (Desv.) Spring possessed potent anti-anoxic effect in the anoxic PC12 cell assay. A phytochemical study of its EtOAc-soluble part led to the isolation of four new and three known biflavonoids. Their structures were established on the basis of physico-chemical properties and spectroscopic analysis. The absolute configurations of the new compounds were determined with the aid of circular dichroism (CD) spectroscopy. Compounds 4 and 5 showed potent anti-anoxic effect in the anoxic PC12 cell assay.

Keywords:

• Selaginella uncinata (Desv.) Spring
• biflavonoids
• anti-anoxic effect
• uncinatabiflavones A–D

Acknowledgements

We are grateful to the National Basic Research Program of China for support of this research (No. 2006CB504100). Thanks are also extended to Professor Q.S. Sun (Shenyang Pharmaceutical University, Shenyang, China) for identifying the plant materials, and to Dr H. Gao, Dr X. Zhang, X. L. Wang, and J.H. Huang (Shenzhen Research Center of Traditional Chinese Medicines and Natural Products, Shenzhen, China) for measuring ESIMS and NMR measurements.