Compounds from the heartwood of Caesalpinia sappan and their anti-inflammatory activity

Two new phenolics, (3S,4R)-3,7,2′,3′-tetrahydroxy-3,4-dihydro-9H-indeno[6,5-c]chromene (caesalpiniaphenol E, 1), and (3R,4S)-3,7-dihydroxy-3-(3′-methoxy-4′-hydroxyphenyl)-4-methoxychroman (caesalpiniaphenol F, 2), together with eleven known compounds (3–13), were isolated from the heartwood of Caesalpinia sappan. Their chemical structures were established mainly by 1D and 2D NMR techniques and mass spectrometry. Their anti-inflammatory activity was evaluated against LPS-induced NO production in macrophage RAW264.7 cells. Among them, compounds 10 and 13 showed strong inhibitory activities toward the LPS-induced NO production in macrophage RAW264.7 cells, with IC50 values of 12.5 and 8.1μm, respectively. Two new phenolics, (3S,4R)-3,7,2′,3′-tetrahydroxy-3,4-dihydro-9H-indeno[6,5-c]chromene (caesalpiniaphenol E, 1), and (3R,4S)-3,7-dihydroxy-3-(3′-methoxy-4′-hydroxyphenyl)-4-methoxychroman (caesalpiniaphenol F, 2), together with eleven known compounds (3–13), were isolated from the heartwood of Caesalpinia sappan. Their chemical structures were established mainly by 1D and 2D NMR techniques and mass spectrometry. Their anti-inflammatory activity was evaluated against LPS-induced NO production in macrophage RAW264.7 cells. Among them, compounds 10 and 13 showed strong inhibitory activities toward the LPS-induced NO production in macrophage RAW264.7 cells, with IC50 values of 12.5 and 8.1μm, respectively. In addition, compounds 10 and 13 inhibited the inductions of iNOS mRNA in dose-dependent manners, indicating that these compounds attenuated the synthesis of these transcripts at the transcriptional level.