Stilbene, 3,4,3 ,5 -tetrahydroxy

Compounds 1 and 2, possessing antitumor and antimetastatic activities, were isolated from the methanol extract. Compounds 1 and 2 were identified as cassigarol A and piceatannol (3, 3 , 4, 5 -tetrahydroxy stilbene), respectively, based on the 1H-NMR spectral data and products... 

Type III PKSs are small, homodimeric enzymes which can be found in both plants and a wide array of microbes. They generally construct fairly low molecular weight 1-2 ring aromatic molecules.36 Examples include plant chalcone and stilbene synthases and the S. coelicolor gene tetrahydroxy naphthalene synthase (THNS), each of which has been structurally characterised by X-ray diffraction. These enzymes are often easy to express het-erologously in E. coli and much work has been done to understand their complicated enzymology as a model for the larger, more complex Type I and II systems.2... 

Chlorophorin (= 2,4,3, 5 -Tetrahydroxy-4 -geranylstilbene) (stilbene, phenolic) Artocarpus incisus (Moraceae) [leaf] 5aR (37)... 

As shown in "Table (4)", it was found that administration of peroxidized com oil for 2 weeks caused liver injury with elevation of GOT and GPT as compared to the control rats. In peroxidized com oil-fed rats, simultaneous oral administration of 2,3,5,4 -tetrahydroxystilbene-2-(9-D-glucoside (50 mg or 100 mg/kg) inhibited the elevation of both GOT and GPT levels. The serum GPT level was also found to be reduced in rats orally given piceid (100 mg/kg) as compared to the peroxidized oil-fed rats. As shown in "Fig. (22)", lipid peroxide (LPO) content in the liver was lowered by the oral administration of 2,3,5,4 -tetrahydroxystilbene-2-(9-D-glucoside (50 mg or 100 mg/kg) or piceid (100 mg/kg) as compared to the peroxidized oil-treated group. Stilbenes such as resveratrol, piceid and 2,3,5,4 -tetrahydroxy-stilbene-2-(9-D-glucoside inhibited NADPH plus ADP-induced lipid peroxidation in rat liver microsomes dose-dependently "Fig. (23)". 

Therefore, two possible mechanisms can be suggested for the protective actions of stilbenes such as piceid and 2,3,5,4 -tetrahydroxy-stilbene-2-O-D-glucoside against liver injury. One is that these stilbenes inhibit further production of lipid peroxide in rats fed the peroxidized oil. The other is that these stilbenes inhibit the destructive actions of lipid peroxide on liver cells. 

The methodology for the synthesis of bibenzyls employs stilbenes as key elements. Usually, the synthesis of bibenzyls could be based on the synthesis of stilbenes by one more step of catalyzed hydrogenation, for instance, the synthesis of bibenzyl 141 [78] and 2-earboxyl-3,2, 4, 5 -tetrahydroxy-bibenzyl [423]. 

Many natural stilbene glycosides have also been reported to have significant antioxidant activities, for example, (Z)-astringin and ( )-and (Z)-resveratrol-4 -0-6-D-glucopyranoside [478], astringin [479], 2,3,4, 5-tetrahydroxy stilbene-2-0-6-D-glucopyranoside [20], compounds 51 [28], 53 [11], 61 and 62 [500]. 

The stilbenes from the bark of Yucca periculosa F. Baker had growth regulatory activity against the Fall Army worm, an insect pest of com. 3,3, 5,5 -Tetrahydroxy-4-methoxystilbene was found to be the most active compound showing significant effect at 3 pg/g in diets. The results indicate the possible correlation of some antioxidant activities with insect growth and development [498],... 

T)-7"-hydroxy-3",7"-dimethyloct-2"-enyl]-2, 3,4, 5- tetrahydroxy-frans-stilbene Chlorophora excelsa 51... 

The drug contains lecithin, several anthraquinones (chrysophanol, emodin, rhein, physicon and chrysophanolanthrone), 2,3,4,5-tetrahydroxy-stilbene-2-0-P-D-glucoside, and is rich in trace elements for example Ca, Fe, Zn, Mn, Cu, Sr [84]. 

Piceatannol 3 -glucoside (astringin) Piceatannol 4 -glucoside Piceatannol 3 -methoxy Chlorophorin 2,4,3, 5 -tetrahydroxy-4 (3,7-di-methyl-2,6-octadienyl)-stilbene 3,4,5,3, 5 -Pentahydroxystilbene Dihydrostilbenes... 

King F E, King T J, Godson D H, Manning L C 1956 The chemistry of extractives from hardwoods. Part XXVII. The occurrence of 3,4,3, 5 -tetrahydroxy- and 3,4,5,3, 5 -pentahydroxy-stilbene in Vouacapoua species. J Chem Soc 4477-4480... 

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