Anti-inflammatory 2-(2-phenylethyl)chromone derivatives from Chinese agarwood.

Five new 2-(2-phenylethyl)chromone derivatives (1-5), along with eleven known compounds (6-16) were isolated from Chinese agarwood. Their structures were elucidated by spectroscopic data (NMR, UV, IR, and MS) analyses and comparison of their spectroscopic and physical data with the literature values. The absolute configurations of 2-4 were determined by electronic circular dichroism (ECD) calculations. Compounds 2-4, 11, 12, and 15 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells with IC50 values in the range 1.6-7.3μM.