New Cassane-Type Diterpenoids of Caesalpinia echinata (Leguminosae) Exhibiting NF-κB Inhibitory Activities

Abstract

Seven new cassane-type diterpenoids, echinalides A–G (1–7), were isolated from the stem of Caesalpinia echinata LAM. (Leguminosae). The structures were established on the basis of their chemical properties and spectroscopic evidence, including two dimensional (2D)-NMR analysis. These compounds were assessed for inhibitory activity against nuclear factor κB (NF-κB). Echinalides C and D, in particular, significantly inhibited NF-κB-responsive reporter gene expression at 5.0 µM, an effect almost equivalent to that of parthenolide, a known potent inhibitor of NF-κB.