Pulcherrins D-R, potential anti-inflammatory diterpenoids from the roots of Caesalpinia pulcherrima

Bioactivity-guided isolation and purification of the dichloromethane extract from the roots of Caesalpinia pulcherrima yielded 15 new cassane-type diterpenes, named pulcherrins D-R (1-15) together with eight known compounds. The structures of the new metabolites were determined on the basis of spectroscopic analyses including 10- and 2D-NMR and mass spectroscopy. The anti-inflammatory activity of isolated compounds was investigated with the lipopolysaccharide (LPS)-induced murine macrophage RAW 264.7 cell lines. Compounds 8, 9, 11-15, and 17-23 showed potent NO inhibitory activity. (C) 2011 Elsevier Ltd. All rights reserved.