62502-00-5Relevant academic research and scientific papers
Antioxidant constituents from rhubarb: Structural requirements of stilbenes for the activity and structures of two new anthraquinone glucosides
Matsuda, Hisashi,Morikawa, Toshio,Toguchida, Iwao,Park, Ji-Young,Harima, Shoichi,Yoshikawa, Masayuki
, p. 41 - 50 (2007/10/03)
The methanolic extracts from five kinds of rhubarb were found to show scavenging activity for DPPH radical and ·O2-. Two new anthraquinone glucosides were isolated from the rhizome of Rheum undulatum L. together with two anthraquinone glucosides, a naphthalene glucoside, and 10 stilbenes. In the screening test for radical scavenging activity of rhubarb constituents, stilbenes and a naphthalene glucoside showed activity, but anthraquinones and sennosides did not. In addition, most stilbenes inhibited lipid peroxidation of erythrocyte membrane by tert-butyl hydroperoxide. Detailed examination of the scavenging effect on various related compounds suggested the following structural requirements; 1) phenolic hydroxyl groups are essential to show the activity; 2) galloyl moiety enhances the activity; 3) glucoside moiety reduces the activity; 4) dihydrostilbene derivatives maintain the scavenging activity for the DPPH radical, but they show weak activity for ·O2-. In addition, several stilbenes with both the 3-hydroxyl and 4′-methoxyl groups inhibited xanthine oxidase.
Inhibitors from rhubarb on lipopolysaccharide-induced nitric oxide production in macrophages: Structural requirements of stilbenes for the activity
Kageura, Tadashi,Matsuda, Hisashi,Morikawa, Toshio,Toguchida, Iwao,Harima, Shoichi,Oda, Mamiko,Yoshikawa, Masayuki
, p. 1887 - 1893 (2007/10/03)
By bioassay-guided separation, three stilbenes (rhapontigenin, piceatannol, and resveratrol), two stilbene glucoside gallates (rhaponticin 2″-O-gallate and rhaponticin 6″-O-gallate), and a naphthalene glucoside (torachrysone 8-O-β-D-glucopyranoside) with inhibitory activity against nitric oxide (NO) production in lipopolysaccharide-activated macrophages were isolated (IC50=11-69μM). The oxygen functions (-OH, -OCH3) of stilbenes at the benzene ring were essential for the activity. The glucoside moiety reduced the activity, while the α,β-double bond had no effect. Furthermore, the active stilbenes (rhapontigenin, piceatannol, and resveratrol) did not inhibit inducible NO synthase activity, but they inhibited nuclear factor-κB activation following expression of iNOS. Copyright
ANTI-LEUKAEMIC COMPOUNDS DERIVED FROM STILBENES IN PICEA ABIES BARK
Mannila, Erkki,Talvitie, Antti,Kolehmainen, Erkki
, p. 813 - 816 (2007/10/02)
Resveratrol was identified and isolated as a minor stilbene derivative from the bark of Picea abies.Three derivatives of resveratrol and three additional derivatives of primary stilbenes from P. abies bark were prepared.Improvement over piceatannol in ant
