Carbazole alkaloids from the stems of Clausena excavata

Abstract

A new carbazole alkaloid, sansoakamine (8), together with 11 known compounds, was isolated from the stems of Clausena excavata. All structures were elucidated by spectroscopic methods. Compound 7 showed moderate anti-malarial activity against Plasmodium falciparum with a MIC value of 6.74 μg/ml.

Keywords:

• Clausena excavata
• carbazole alkaloids
• Rutaceae
• sansoakamine

Acknowledgements

We would like to thank the Biodiversity Research and Training Program (Grant No. BRT T651176) and Mae Fah Luang University, Chiang Rai, Thailand for research grants. We are grateful to Assoc. Prof. Dr Uma Prawat and Ms Nareerat Thongtip, Phuket Rajabhat University, for correcting the NMR spectral data.