Platelet-activating factor (PAF)receptor binding antagonists from Alpinia officinarum 

 -  Bioorganic & Medicinal Chemistry Letters, 17(24), p.6720-6722, 2007 .
<br/><br/> The bioassay-guided purification of ether extracts of Alpinia officinarum led to the isolation of two new compounds 6- xydroxy-1,7-diphenyl-4-en-3-heptanone (1)and 6-(2-hydroxy-phenyl)-4-methoxy-2-pyrone (4)as well as three known compounds 1,7-diphenyl-4-en-3-heptanone (2), 1,7-diphenyl-5-methoxy-3-heptanone (3), and apigenin (5). Their structures were established on the basis of spectral methods. All three diarylheptanoids 1, 2, and 3 exhibited potent PAF receptor binding inhibitory activities with an IC50 of 1.3, 5.0, and 1.6 lM, respectively. These studies have identified diarylheptanoids as a novel class of potent PAF antagonists.