Lignans with anti-inflammatory activity from the roots of Rosmarinus officinalis

Eight lignans and four phenylpropanoids were isolated and identified from the roots of Rosmarinus officinalis, three of which were previously unreported compounds. Their structures were elucidated through comprehensive spectroscopic analyses, including HRESIMS, NMR, UV, IR, and ECD calculations. The new compounds were designated as rosmarinicols A-C (1-3). The anti-inflammatory activities of all the compounds were assessed using an LPS-induced RAW264.7 mouse macrophage model. The results showed that compounds 3, 5, 8, 9, 11, and 12 inhibited the production of NO in a dose-dependent manner at concentrations of 2.5, 5, and 10 μM, with IC₅₀ values of 21.98, 5.01, 6.91, 4.43, 12.65, and 7.11 μM, respectively. This study demonstrates that the roots of Rosmarinus officinalis are rich in lignans with promising anti-inflammatory lignans properties, providing a scientific basis for further research and potential development.