Lignanamides from the Roots of Metternichia macrocalyx and Their Anti-inflammatory Activity

Five new lignanamides (1-5) and ten known amides (6-15) were isolated from the chloroform extract of Metternichia macrocalyx roots. The structures of the new compounds were elucidated via analysis of NMR spectroscopic and mass spectrometry data and known structures by comparison with data from the literature. Compound 1 had its absolute configuration established through ECD experiments, NMR calculations and quantum mechanical calculations. The anti-inflammatory activity of compounds (1-5) was assessed on RAW 264.7 macrophages. All the tested compounds reduced nitric oxide levels. In the cytokine quantification assays, only compound 2 did not significantly reduce IL-10 levels. Moreover, compounds 1-3 and 5 also reduced IL-1β levels. These results suggest the anti-inflammatory potential of these compounds.