Anti-inflammatory dimeric furanocoumarins from the roots of Angelica dahurica

Seven new dimeric furanocoumarins, dahuribiethrins A-G (1-7), were isolated from the roots of Angelica dahurica. Their structures were determined by chemical derivatization and extensive spectroscopic techniques, including H-1 NMR, C-13 NMR, HSQC, H-1-H-1 COSY, HMBC, and NOESY experiments. Compounds 2, 3, 4, and 5 exhibited significant inhibition of nitric oxide production in the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells with IC50 values in the range of 8.8-9.8 mu M. (C) 2015 Elsevier B.V. All rights reserved.