Guaianolide-type sesquiterpene lactones from Achillea millefolium L. and their anti-inflammatory activity

Seventeen undescribed guaianolide sesquiterpene lactones, millefoliumines A-Q, and seven known analogues were isolated from the whole plant of Achillea millefolium L. growing in Xinjiang, China. Their structures were elucidated based on the HRESIMS and NMR data analyses. The absolute configurations of millefoliumines A-Q were determined by single-crystal X-ray crystallography, ECD data analysis along with quantum-chemical ECD calculations. The anti-inflammatory effects of these compounds on the LPS-induced RAW264.7 cell model were evaluated. As a result, millefoliumine G exhibited potential inhibitory effects on the release of NO, the level of pro-inflammatory cytokines including TNF-α and IL-6. Above results indicated a potential of the guaianolides from A. millefolium in the anti-inflammatory drug development.