|Nat Prod Commun. 2014 Jan;9(1):79-82. |
|Antiausterity activity of arctigenin enantiomers: importance of (2R,3R)-absolute configuration[Pubmed: 24660468]|
METHODS AND RESULTS:
From a MeOH extract of powdered roots of Wikstroemia indica, six dibenzyl-gamma-butyrolactone-type lignans with (2S,3S)-absolute configuration [(+)-arctigenin (1), (+)-Matairesinol (2), (+)-trachelogenin (3), (+)-nortrachelogenin (4), (+)-hinokinin (5), and (+)-kusunokinin (6)] were isolated, whereas three dibenzyl-gamma-butyrolactone-type lignans with (2R,3R)-absolute configuration [(-)-arctigenin (1*), (-)-matairesinol (2*), (-)-trachelogenin (3*)] were isolated from Trachelospermum asiaticum. The in vitro preferential cytotoxic activity of the nine compounds was evaluated against human pancreatic PANC-1 cancer cells in nutrient-deprived medium (NDM), but none of the six lignans (1-6) with (2S,3S)-absolute configuration showed preferential cytotoxicity. On the other hand, three lignans (1*-3*) with (2R,3R)-absolute configuration exhibited preferential cytotoxicity in a concentration-dependent manner with PC50 values of 0.54, 6.82, and 5.85 microM, respectively. Furthermore, the effect of (-)- and (+)-arctigenin was evaluated against the activation of Akt, which is a key process in the tolerance to nutrition starvation. Interestingly, only (-)-arctigenin (1*) strongly suppressed the activation of Akt.
These results indicate that the (2R,3R)-absolute configuration of (-)-enantiomers should be required for the preferential cytotoxicity through the inhibition of Akt activation.
|Yao Xue Xue Bao. 2001 Sep;36(9):669-71. |
|New biflavanones and bioactive compounds from Stellera chamaejasme L.[Pubmed: 12580104]|
|To study the chemical constituents of the root of Stellera chamaejasme L. |
METHODS AND RESULTS:
Various column chromatographies on silica gel and RP-18 were employed for isolation and purification. Structures of compounds were elucidated by spectral analysis. Eight lignans and three biflavonoids possessing a C-3/C-3" linkage were isolated. They are ruixianglangdusu A (1) and B (2), 4',4'",5,5",7,7"-hexahydroxy-3,3"-biflavone (3), (+)-kusunokinin (4), lirioresinol-B (5), magnolenin C (6), (-)-pinoresinol monomethyl ether (7), (-)-pinoresinol (8), (+)-Matairesinol (9), isohinokinin (10) and (-)-eudesmin (11).
Compounds 1 and 2 are new biflavanones, 1 is enantiomeric to known chamaejasmenin C, 4, 6, 8, 9, 10 and 11 were isolated from this plant for the first time, and 7 was isolated from natural resources for the first time. In vitro bioassays showed that 3 and 8 exhibited antibacterial activity, and 1, 2, 9 and 11 exhibited immunomodulatory activity.