Phenolic compounds from Caesalpinia sappan heartwood and their anti-inflammatory activity

Four new phenolic compounds, caesalpiniaphenols A-D (1-4), together with eight known compounds were isolated from Caesalpinia sappan heartwood. The chemical structures were established mainly by NMR, MS, ECD, and Mosher's method. Compounds 4, 5, and 7 showed weak inhibitory activity against the LPS-induced NO production in macrophage RAW264.7 cells with IC(50) values of 12.2, 3.5, and 5.7 μM, respectively.