Flavonoid and a rare benzophenone glycoside from the leaves of Aquilaria sinensis.

From the leaves of Aquilaria sinensis (LOUR.) GILG, a novel benzophenone glucoside, designated as aquilarinoside A (1), and a new flavonoid, as 7-beta-D-glucoside of 5-O-methylapigenin (2), along with eight known compounds (3-10) were isolated. The structures of 1 and 2 were fully characterized by spectroscopic methods (1D, 2D NMR and MS) and the relative stereochemistry was assigned based on nuclear Overhauser effect spectroscopy (NOESY) correlations and analyses of coupling constants. The new compounds showed inhibition activity against polymorphonuclear neutrophils (PMNs) respiratory burst stimulated by PMA.