Diarylheptanoids chemical structures

In this article, we have reviewed the literatures available for the mechanism of action and anti-inflammatory properties of selected nutraceuticals such as curcumin, resveratrol, green tea polyphenols and diarylheptanoids (chemical structures in Figure 1). In addition we have also shown the antiinflammatory properties of a diarylheptanoids from Alpinia galanga and different possible targets in inflammation. 

The 1,7-diarylheptanoids constitute a class of secondary plant metabolites characterised by the structural motif aryl-C7-aryl. The diarylheptanoids appear in both linear and cyclic forms. Based on their chemical structures, the diarylheptanoids have been grouped in five major types [1]. 

Four diarylheptanoids were isolated from the methanol ic extract of the rhizomes of 4. officinarum and identified on the basis of their spectral data and by chemical correlations as l,7-diphenylhept-4-en-3-one (40), 7-(4"-hydroxy-3"-methoxyphenyl)-l-phenylhept-4-en-3-one (41), 1,7-dipheny 1-5-hydroxy-3-heptanone (43) and 5-hydroxy-7-(4"-hydroxy-3"-methoxyphenyl)-l-phenyl-3-heptanone (44) [38]. From the chloroform-soluble fraction of the methanolic extract of the rhizomes of A. officinarum, three new diarylheptanoids, 5-methoxy-7-(4"-hydroxy-3"-methoxyphenyl)-l-phenyl-3-heptanone (46), 5-hydroxy-7-(4"-hydroxyphenyl)- -phenyl-3-heptanone (45) and 7-(4"-hydroxy-3"-methoxyphenyl)- -phenyl-3,5-heptanedione (49) were isolated together with 41, 43 and 44 [39]. Compound 44 was the major constituent of the chloroform-soluble fraction. Compounds 41, 43-46 and 49 showed inhibitory effect against PG synthetase and IC50 values of the compounds were reported [39]. In addition to compounds 43, 44 and 52, three new diarylheptanoids, 42,47 and 48 were isolated from the rhizomes of A. officinarum and the structures were elucidated on the basis of the spectroscopic data [40]. The configuration of C-5 of 43 and 52 was determined to be R and that of hexahydrocurcumin was S [40]. 

A. blepharocalyx has been used as a stomachic in South-west China [49]. Three novel diarylheptanoids, calyxin A (55), calyxin B (56) and epi-calyxin B (57) were isolated from ethanolic extract of the seeds of A. blepharocalyx and their structures were determined by 2D NMR techniques and chemical analysis [49]. These compounds showed a mild 3a-dehydrogenase (3a-HSD) inhibitory activity [49]. Further examination of the same extract yielded two additional diarylheptanoids, blepharocalyxin A (58) and blepharocalyxin B (59) [50]. Compounds 58 and 59 inhibited nitric oxide production in endotoxin-activated murine... 

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