Diarylheptanoids of Curcuma comosa with Inhibitory Effects on Nitric Oxide Production in Macrophage RAW 264.7 Cells

Eight new diarylheptanoids, a 1.2:1 mixture of (3,S)- and (3R)-1-(4-hydroxyphenyl)-7-phenyl-(4E,6E)-4,6-heptadien-3-ol (1a and 1b), a racemic mixture of (35)- and (3R)-1-(4-hydroxyphenyl)-3-methoxy-7-phenyl-(4E,6E)-4,6-heptadiene (2a and 2b), a ca. 1:1 mixture of (3S)- and (3R)-1-(4-hydroxy-3methoxyphenyl)-3-methoxy-7-phenyl)-(4E,6E)-4,6-heptadiene (3a and 3b), 3-acetoxy-1-(3,4-dihydroxyphenyl)-7-phenylheptan-5-ol (4), (3R)-1-(4,5dihydroxyphenyl)-7-phenyl-(6E)-6-hepten-3,2'-epoxide (5), and thirteen known diarylheptanoids, 6-12, a 3:1 mixture of 13a and 13b, and 14-17, were isolated from the rhizomes of Curcuma comosa from Sakon Nakhon, northeastern part of Thailand. The isolated compounds were evaluated for their anti-inflammatory activities on the inhibition of lipopolysaccharide-induced nitric oxide production in macrophage RAW 264.7 cells and the diarylheptanoids la and 1b mixture and 14 exhibited potent inhibitory activity.