Abstract
Five new Erythrina alkaloids and five known E. alkaloids were isolated from a 95% ethanol extract of the stems of Erythrina corallodendron L. Their chemical structures were elucidated by UV, IR, HRESIMS, NMR and X-ray. Furthermore, the analgesic activities of E. alkaloids 1, 2 and 6 were evaluated by using an acetic acid-induced writhing test in mice, and their writhing inhibition rates were 67.9%, 64.6% and 70.3% at doses of 20 mg/kg, respectively.
Graphical Abstract
Acknowledgment
We are grateful to the Department of Instrumental Analysis, Institute of Material Medica, Chinese Academy of Medical Sciences & Peking Union Medical College for performing the IR spectroscopy, NMR spectroscopy, MS and HRESIMS.
Disclosure statement
No potential conflicts of interest were reported by the authors.