- Enzymatic synthesis of catechol-functionalized polyphenols with excellent selectivity and productivity
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Polyphenol products have become more and more attractive due to their strong anti-oxidant properties and a great variety of promising pharmacological activities and beneficial effects on human health. In this study, mushroom tyrosinase immobilized as cross-linked enzyme aggregates (CLEAs) was used as the catalyst for ortho-hydroxylation reactions to produce 3,4-dihydroxyphenylacetic acid, piceatannol and 3′-hydroxypterostilbene from 4-hydroxyphenylacetic acid, resveratrol and pterostilbene, respectively, with excellent selectivity and productivity. This is the first report of synthesizing these three polyphenolic compounds with tyrosinase CLEAs as catalyst, and the first study of biocatalytic production of 3′-hydroxypterostilbene. Introducing a deep eutectic solvent (DES) into the tyrosinase CLEA preparation exhibited a positive effect in terms of enhancing the catalytic activity of the immobilized enzyme and also promoting the synthesis of the polyphenol products.
- Cheng, Hui,Zou, Yong,Luo, Xiang,Song, Xian-Heng,Yang, Zhen
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- Resveratrol analogues as selective cyclooxygenase-2 inhibitors: Synthesis and structure-activity relationship
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A series of hydroxylated and methoxylated trans-stilbenes were synthesized and evaluated for their ability to inhibit COX-1 and COX-2. Some of the hydroxylated derivatives are highly selective COX-2 inhibitor with potency comparable or better than clinically established drugs. Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is found in grapes and various medical plants. Among cytotoxic, antifungal, antibacterial cardioprotective activity resveratrol also demonstrates non-selective cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) inhibition. In order to find more selective COX-2 inhibitors a series of methoxylated and hydroxylated resveratrol derivatives were synthesized and evaluated for their ability to inhibit both enzymes using in vitro inhibition assays for COX-1 and COX-2 by measuring PGE2 production. Hydroxylated but not methoxylated resveratrol derivatives showed a high rate of inhibition. The most potent resveratrol compounds were 3,3′,4′,5-tetra-trans-hydroxystilbene (COX-1: IC50 = 4.713, COX-2: IC50 = 0.0113 μM, selectivity index = 417.08) and 3,3′,4,4′,5,5′-hexa-hydroxy-trans-stilbene (COX-1: IC 50 = 0.748, COX-2: IC50 = 0.00104 μM, selectivity index = 719.23). Their selectivity index was in part higher than celecoxib, a selective COX-2 inhibitor already established on the market (COX-1: IC 50 = 19.026, COX-2: IC50 = 0.03482 μM, selectivity index = 546.41). Effect of structural parameters on COX-2 inhibition was evaluated by quantitative structure-activity relationship (QSAR) analysis and a high correlation was found with the topological surface area TPSA (r = 0.93). Docking studies on both COX-1 and COX-2 protein structures also revealed that hydroxylated but not methoxylated resveratrol analogues are able to bind to the previously identified binding sites of the enzymes. Hydroxylated resveratrol analogues therefore represent a novel class of highly selective COX-2 inhibitors and promising candidates for in vivo studies.
- Murias, Marek,Handler, Norbert,Erker, Thomas,Pleban, Karin,Ecker, Gerhard,Saiko, Philipp,Szekeres, Thomas,J?ger, Walter
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- Regioselective synthesis of piceatannol from resveratrol: Catalysis by two-component flavin-dependent monooxygenase HpaBC in whole cells
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Piceatannol, a valuable biologically active stilbene derivative, was efficiently synthesized from resveratrol. Whole-cell catalysis with HpaBC monooxygenase enabled the regioselective hydroxylation of resveratrol to produce 23 mM (5.2 g L-1) of piceatannol.
- Furuya, Toshiki,Kino, Kuniki
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- Comparative study of radical scavenger and antioxidant properties of phenolic compounds from Vitis vinifera cell cultures using in vitro tests
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Vitis vinifera cell suspensions were used to isolate and characterize the flavonoids (anthocyanins, catechins) and non-flavonoids (stilbenes) found in red wine. Furthermore, we showed that astringin is produced although this stilbene has not previously been reported to be a constituent of V. vinifera or wine. The ability of these compounds to act as radical scavengers was investigated using 1,1-diphenyl-2-picryl-hydrazyl (DPPH), a stable free radical. Antioxidant activities were assessed by their capacity to prevent Fe2+-induced lipid peroxidation in microsomes and their action on Cu2+-induced lipid peroxidation in low-density lipoproteins. The results showed that astringin has an important antioxidant effect similar to that of trans-resveratrol, and a higher radical scavenger activity than the latter. Astringinin appeared to be more active. These data indicate that phenolic compounds (stilbenes, catechins, anthocyanins) exhibit interesting properties which may account in part for the so-called 'French paradox,' i.e. that moderate drinking of red wine over a long period of time can protect against coronary heart disease.
- Fauconneau, Bernard,Waffo-Teguo, Pierre,Huguet, Francois,Barrier, Laurence,Decendit, Alain,Merillon, Jean-Michel
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- Radical-induced oxidation of trans-resveratrol
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trans-Resveratrol (RVT) (3,5,4′-trihydroxystilbene), a polyphenolic constituent of red wine, is thought to be beneficial in reducing the incidence of cardiovascular diseases, partly via its antioxidant properties. However, the mechanism of action by which trans-resveratrol displays its antioxidant effect has not been totally unravelled. This study aimed at establishing a comprehensive scheme of the reaction mechanisms of the direct scavenging of HO and O2- radicals generated by water gamma radiolysis. Aerated aqueous solutions of trans-RVT (from 10 to 100 μmol L-1) were irradiated with increasing radiation doses (from 25 to 400 Gy) and further analyzed by UV-visible absorption spectrophotometry for detection of trans-RVT oxidation products. Separation and quantification of RVT and its four oxidation products previously identified by mass spectrometry, i.e., piceatannol (PCT), 3,5-dihydroxybenzoic acid (3,5-DHBA), 3,5-dihydroxybenzaldehyde (3,5-DHB) and para-hydroxybenzaldehyde (PHB), were performed by HPLC/UV-visible spectrophotometry. Determination of the radiolytic yields of trans-RVT consumption and oxidation product formation has allowed us to establish balance between trans-RVT disappearance and the sum of oxidation products formation. Under our conditions, O2- radicals seemed to poorly initiate oxidation of trans-RVT, whereas the latter, whatever its initial concentration, quantitatively reacted with HO radicals, via a dismutation mechanism. Two reaction pathways involving HO-induced trans-RVT primary radicals have been proposed to explain the formation of the oxidation end-products of trans-RVT.
- Camont, Laurent,Collin, Fabrice,Couturier, Martine,Thérond, Patrice,Jore, Daniel,Gardès-Albert, Monique,Bonnefont-Rousselot, Dominique
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- Liquid chromatographic/electrospray ionization mass spectrometric identification of the oxidation end-products of trans-resveratrol in aqueous solutions
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trans-Resveratrol (3,5,4′-trihydroxystilbene) is a natural polyphenolic compound that exhibits antioxidant properties. Our study aimed at studying the HO*-induced oxidation of resveratrol (100 μmol.L-1) in aerated aqueous solutions. Gamma radiolysis of water was used to generate HO*/O2- free radicals (I=10 Gy.min-1, dose=400 Gy). Oxidation products were identified by direct infusion mass spectrometry and high-performance liquid chromatography/mass spectrometry. For each product, structural elucidation was based on simple mass spectra, fragmentation spectra and deuterium/hydrogen exchange spectra; the comparison with mass spectra of synthetic products provided valuable information allowing the complete identification of the oxidation products. Four products resulting from the direct attack of HO. radicals towards resveratrol were identified respectively as piceatannol (trans-3,5,3′,4′-tetrahydroxystilbene), 3,5-dihydroxybenzoic acid, 3,5-dihydroxybenzaldehyde and 4-hydroxybenzaldehyde.
- Camont, Laurent,Collin, Fabrice,Marchetti, Catherine,Jore, Daniel,Gardes-Albert, Monique,Bonnefont-Rousselot, Dominique
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- Production of anti-cancer agent using microbial biotransformation
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Microbial biotransformation is a great model system to produce drugs and biologically active compounds. In this study, we elucidated the fermentation and production of an anti-cancer agent from a microbial process for regiospecific hydroxylation of resveratrol. Among the strains examined, a potent strain showed high regiospecific hydroxylation activity to produce piceatannol. In a 5 L (w/v 3 L) jar fermentation, this wild type Streptomyces sp. in the batch system produced 205 mg of piceatannol (i.e., 60% yields) from 342 mg of resveratrol in 20 h. Using the product, an in vitro anti-cancer study was performed against a human cancer cell line (HeLa). It showed that the biotransformed piceatannol possessed a significant anticancer activity. This result demonstrates that a biotransformation screening method might be of therapeutic interest with respect to the identification of anti-cancer drugs.
- Roh, Changhyun,Kang, Chankyu
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- Protective effect of piceatannol and bioactive stilbene derivatives against hypoxia-induced toxicity in H9c2 cardiomyocytes and structural elucidation as 5-LOX inhibitors
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Stilbenes with well-known antioxidant and antiradical properties are beneficial in different pathologies including cardiovascular diseases. The present research was performed to investigate the potential protective effect of resveratrol (1) and piceatannol (2), against hypoxia-induced oxidative stress in the H9c2 cardiomyoblast cell line, and the underlying mechanisms. Compounds 1 and 2 significantly inhibited the release of peroxynitrite and thiobarbituric acid levels at na no- or submicromolar concentrations, and this effect was more evident in piceatannol-treated cells, that significantly increased MnSOD protein level in a concentration dependent manner. Furthermore, since piceatannol, which is far less abundant in natural sources, displayed a higher bioactivity than the parent compound, we hereby report on a very fast synthesis and detailed structure-based design of a focused stilbene library. Finally, taking into account that hypoxia-induced ROS accumulation also increases expression and activity of 5-lipoxygenase (5-LOX) with production of leukotrienes, we have disclosed structural key factors crucial for 5-LOX activity. Among the synthesized analogues (3–7), compound 7 was the most effective in improving cardiomyocytes viability and in 5-LOX inhibition. In conclusion, modeling and experimental studies provided the basis for further optimization of stilbene analogues as multi-target inhibitors of the inflammatory and oxidative pathway.
- Boccellino, Mariarosaria,Donniacuo, Maria,Bruno, Ferdinando,Rinaldi, Barbara,Quagliuolo, Lucio,Ambruosi, Marika,Pace, Simona,De Rosa, Mario,Olga?, Abdurrahman,Banoglu, Erden,Alessio, Nicola,Massa, Antonio,Kahn, Haroon,Werz, Oliver,Fiorentino, Antonio,Filosa, Rosanna
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- A focused multiple reaction monitoring (MRM) quantitative method for bioactive grapevine stilbenes by ultra-high-performance liquid chromatography coupled to triple-quadrupole mass spectrometry (UHPLC-QqQ)
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Grapevine stilbenes are a family of polyphenols which derive from trans-resveratrol having antifungal and antimicrobial properties, thus being considered as phytoalexins. In addition to their diverse bioactive properties in animal models, they highlight a strong potential in human health maintenance and promotion. Due to this relevance, highly-specific qualitative and quantitative methods of analysis are necessary to accurately analyze stilbenes in different matrices derived from grapevine. Here, we developed a rapid, sensitive, and specific analysis method using ultra-high-performance liquid chromatography coupled to triple-quadrupole mass spectrometry (UHPLC-QqQ) in MRM mode to detect and quantify five grapevine stilbenes, trans-resveratrol, trans-piceid, trans-piceatannol, trans-pterostilbene, and trans-?-viniferin, whose interest in relation to human health is continuously growing. The method was optimized to minimize in-source fragmentation of piceid and to avoid co-elution of cis-piceid and trans-resveratrol, as both are detected with resveratrol transitions. The applicability of the developed method of stilbene analysis was tested successfully in different complex matrices including cellular extracts of Vitis vinifera cell cultures, reaction media of biotransformation assays, and red wine.
- Hurtado-Gaitán, Elías,Sellés-Marchart, Susana,Martínez-Márquez, Ascensión,Samper-Herrero, Antonio,Bru-Martínez, Roque
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- Biomimetic preparation of the racemic modifications of the stilbenolignan aiphanol and three congeners
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A chromatographically separable mixture of the racemic modification, (±)-1, of the stilbenolignan (-)-aiphanol and congeners (±)-2-4 has been generated by a silver(I)-mediated and potentially biomimetic oxidative coupling of piceatannol (5) with sinapic a
- Chand, Satish,Banwell, Martin G.
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- Regioselective hydroxylation of trans -resveratrol via inhibition of tyrosinase from streptomyces avermitilis MA4680
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Secreted tyrosinase from melanin-forming Streptomyces avermitilis MA4680 was involved in both ortho-hydroxylation and further oxidation of trans-resveratrol, leading to the formation of melanin. This finding was confirmed by constructing deletion mutants of melC2 and melD 2 encoding extracellular and intracellular tyrosinase, respectively; the melC2 deletion mutant did not produce piceatannol as well as melanin, whereas the melD2 deletion mutant oxidized resveratrol and synthesized melanin with the same yields, suggesting that MelC2 is responsible for ortho-hydroxylation of resveratrol. Extracellular tyrosinase (MelC2) efficiently converted trans-resveratrol into piceatannol in the presence of either tyrosinase inhibitors or reducing agents such as catechol, NADH, and ascorbic acid. Reducing agents slow down the dioxygenase reaction of tyrosinase. In the presence of catechol, the regio-specific hydroxylation of trans-resveratrol was successfully performed by whole cell biotransformation, and further oxidation of trans-resveratrol was efficiently blocked. The yield of this ortho-hydroxylation of trans-resveratrol was dependent upon inhibitor concentration. Using 1.8 mg of wild-type Streptomyces avermitilis cells, the conversion yield of 100 μM trans-resveratrol to piceatannol was 78% in 3 h in the presence of 1 mM catechol, indicating 14 μM piceatannol h-1 DCW mg-1 specific productivity, which was a 14-fold increase in conversion yield compared to that without catechol, which is a remarkably higher reaction rate than that of P450 bioconversion. This method could be generally applied to biocatalysis of various dioxygenases.
- Lee, Nahum,Kim, Eun Jung,Kim, Byung-Gee
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- Nickel(II)-Catalyzed Borylation of Alkenyl Methyl Ethers via C-O Bond Cleavage
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A new protocol has been developed for the borylation of conjugated alkenyl methyl ethers using B2Pin2 via C-O bond cleavage catalyzed by Ni(II). In this cross-coupling reaction, both E/Z isomers of alkenyl ethers are converted into (E)-alkenyl boronic esters with good reactivity. This transformation exhibits high chemoselectivity in the presence of competitive C-O bonds such as aryl ether, ester, amide, and thioether groups, thus providing a new method for the construction of various alkenyl boronates.
- Qiu, Xiaodong,Li, Yangyang,Zhou, Li,Chen, Peishan,Li, Fan,Zhang, Yanan,Ling, Yong
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supporting information
p. 6424 - 6428
(2020/08/24)
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- Inhibition of Pancreatic α-amylase by Resveratrol Derivatives: Biological activity and molecular modelling evidence for cooperativity between viniferin enantiomers
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To improve the current understanding of the role of stilbenoids in the management of diabetes, the inhibition of the pancreatic α-amylase by resveratrol derivatives was investigated. To approach in a systematic way, the mechanistic and structural aspects of the interaction, potential bioactive agents were prepared as single molecules, that were used for the biological evaluation of the determinants of inhibitory binding. Some dimeric stilbenoids—in particular, viniferin isomers— were found to be better than the reference drug acarbose in inhibiting the pancreatic α-amylase. Racemic mixtures of viniferins were more effective inhibitors than the respective isolated pure enantiomers at an equivalent total concentration, and displayed cooperative effects not observed with the individual enantiomers. The molecular docking analysis provided a thermodynamics-based rationale for the measured inhibitory ability and for the observed synergistic effects. Indeed, the binding of additional ligands on the surface of the alpha-amylase was found to decrease the dissociation constant of inhibitors bound to the active site of the enzyme, thus providing a mechanistic rationale for the observed inhibitory synergies.
- Mattio, Luce M.,Marengo, Mauro,Parravicini, Chiara,Eberini, Ivano,Dallavalle, Sabrina,Bonomi, Francesco,Iametti, Stefania,Pinto, Andrea
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- Preparation method of resveratrol compound
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The invention provides a preparation method of a resveratrol compound, and belongs to the technical field of organic synthesis. The preparation method comprises the following steps: firstly, carryingout oxidation addition and reduction elimination reaction on alkoxy-substituted benzyl halide, alkoxy-substituted benzaldehyde and a metal catalyst to obtain alkoxy-substituted diacetophenone; then carrying out reduction, reverse elimination and selective debenzylation reaction on the alkoxy-substituted diacetophenone and the metal catalyst in a hydrogen atmosphere to obtain the resveratrol compound. In the preparation method, hydrogenation reduction, reverse elimination and selective debenzylation reaction can be achieved through a one-pot method, trans-olefin is directly obtained through thereaction, and the generation of isomers is avoided; the Lewis acid is removed from the source through the selective catalytic debenzylation of the reaction, so that the method has the advantage of high yield, and is an environment-friendly process. Experimental results show that the products obtained by the preparation method are trans-olefins, the purity can reach more than 99.5%, and the yieldis more than 80%.
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Paragraph 0064; 0065
(2019/07/16)
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- Synthesis method of piceatannol
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The invention provides piceatannol. A target product piceatannol is prepared through the steps of taking 3-hydroxyl-4-methoxybenzaldehyde as a starting raw material, carrying out wittig reaction to generate 3-hydroxyl-4-methoxystyrene, carrying out Heck r
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- Synthesis of resveratrol derivatives as new analgesic drugs through desensitization of the TRPA1 receptor
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A series of 31 resveratrol derivatives was designed, synthesized and evaluated for activation and inhibition of the TRPA1 channel. Most acted as activators and desensitizers of TRPA1 channels like resveratrol or allyl isothiocyanate (AITC). Compound 4z (HUHS029) exhibited higher inhibitory activity than resveratrol with an IC50 value of 16.1?μM. The activity of 4z on TRPA1 was confirmed in TRPA1-expressing HEK293 cells, as well as in rat dorsal root ganglia neurons by a whole cell patch clamp recording. Furthermore, pretreatment with 4z exhibited an analgesic effect on AITC-evoked TRPA1-related pain behavior in vivo.
- Nakao, Syuhei,Mabuchi, Miyuki,Wang, Shenglan,Kogure, Yoko,Shimizu, Tadashi,Noguchi, Koichi,Tanaka, Akito,Dai, Yi
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p. 3167 - 3172
(2017/06/13)
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- Synthetic method for piceatannol derivatives and pharmaceutical compounds containing the piceatannol derivatives
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The piceatannol derivatives were easily synthesized using a Wittig-Horner reaction, a Colvin rearrangement and a Sonogashira reaction. According to the result of investigating the anti-inflammatory activity of compounds synthesized in RAW264.7 macrophages induced by LPS, compounds 6 to 8 showed remarkable activity at the concentration of 10 andmu;M, and a compound 7 (90.1%), a compound 8 (60.8%) and a compound 6 (55.2%) showed no cytotoxicity. The present invention aims to provide a method for efficiently synthesizing the piceatannol derivatives and to confirm the biological activity of synthesized piceatannol derivatives.COPYRIGHT KIPO 2017
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- Method for synthesizing artificially all-trans-resveratrol and derivative thereof
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The invention discloses a method for synthesizing artificially all-trans-resveratrol and a derivative thereof. In the method, the precursors of all-trans-resveratrol and the derivative thereof are prepared by means of constructing a conjugated fused ring, thus the all-trans-spatial structure of resveratrol and the derivative thereof is restricted completely, to prepare all-trans-resveratrol and the derivative thereof. The resulting product of the preparation method of 1,2-stilbene or the derivative thereof in the invention is of all-trans configuration, so as to meet the demand of biologically active substance chemicals. Compared to the previous processes, the method provided by the invention has the advantages of simple processes and mild conditions, thereby meeting the green chemistry concept.
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Paragraph 0036; 0037
(2017/08/31)
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- A method for the synthesis of hydroxy [...] composition of the new method (by machine translation)
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The present invention discloses a new method for the synthesis of hydroxy [...] compound. The claimed method is: in the organic solvent, under a certain temperature, ammonium formate/through the palladium catalytic removal of benzyl protecting group system, to obtain hydroxyl [...] compound. The method has the mild reaction conditions, the operation is simple, small reagent toxicity, safety, high yield, wide range of application, low cost, relatively suitable for mass production and the like. (by machine translation)
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Paragraph 0079-0080
(2017/08/27)
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- CATECHOL DERIVATIVES PREPARED BY USING TYROSINASE, METHOD FOR PREPARATION THEREOF, AND APPLICATION THEREOF
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The present invention refers to using tyrosinase and pyrocatechole type structural material technology and exclusively on the basis of the response in the biosynthesis of, melanocyte secondary oxidation reaction by effectively inhibiting, mono phenol type primary structural material optionally catalyst only complex induced a are defined.. The present invention refers to using the same variety of functional pyrocatechole type materials, with high productivity and. there is provided a technique for production yield. (by machine translation)
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Paragraph 0077; 0078
(2016/12/12)
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- Method of preparing piceatannol using bacterial cytochrome P450 and composition therefor
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Provided is a method of preparing piceatannol, and more particularly, to a method of preparing piceatannol from resveratrol using bacterial cytochrome P450 BM3 (CYP102A1) or mutants thereof, and a composition and a kit therefor.
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(2015/09/28)
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- CAJANINE STRUCTURE ANALOGOUS COMPOUND, PREPARATION METHOD AND USE
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Provided are cajanine structure analogous compounds, synthesis method and pharmacological effects thereof, the compounds of the present invention having the structure as represented by general formulas I, II, III, IV and V. Also provided are pharmaceutical compositions containing the compounds as active ingredient, and uses thereof; the compounds of the present invention having the pharmacological activities such as anti-virus, anti-virus-infection, nerve protection, anti-metabolic-diseases and the like. Also provided is a chemical total synthesis preparation method of the natural products cajanine, cajanine A and cajanine C. The present invention lays a foundation for the in-depth study and development of the compounds as clinical drugs in the future.
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Paragraph 0239
(2014/11/13)
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- CAJANINE STRUCTURE ANALOGOUS COMPOUND, PREPARATION METHOD AND USE
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Provided are cajanine structure analogous compounds, synthesis method and pharmacological effects thereof, the compounds of the present invention having the structure as represented by general formulas I, II, III, IV and V. Also provided are pharmaceutical compositions containing the compounds as active ingredient, and uses thereof; the compounds of the present invention having the pharmacological activities such as anti-virus, anti-virus-infection, nerve protection, anti-metabolic-diseases and the like. Also provided is a chemical total synthesis preparation method of the natural products cajanine, cajanine A and cajanine C. The present invention lays a foundation for the in-depth study and development of the compounds as clinical drugs in the future.
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Paragraph 0086; 0250
(2015/01/06)
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- Dimerization of piceatannol by Momordica charantia peroxidase and α-glucosidase inhibitory activity of the biotransformation products
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Stilbenes, especially those oligomers, have great potential to be antihyperglycemic agents. In this study, eight stilbene dimers, including five new ones, were obtained by biotransformation of piceatannol using Momordica charantia peroxidase (MCP) for the first time. Their structures were established on the basis of spectroscopic evidences. These piceatannol dimers displayed potential α-glucosidase inhibitory activities, and trans double bond, tetrahydrofuran ring, and free adjacent phenolic dihydroxyls were found to be important for their activities. Enzymatic biotransformation of stilbenes by M. charantia peroxidase (MCP) was showed to be a prominent way to produce oligomeric stilbenes for antihyperglycemic development.
- Wan, Xiang,Wang, Xiao-Bing,Yang, Ming-Hua,Wang, Jun-Song,Kong, Ling-Yi
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p. 5085 - 5092
(2011/10/08)
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- Efficient synthesis of natural polyphenolic stilbenes: Resveratrol, piceatannol and oxyresveratrol
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The practical synthesis of important natural polyphenolic stilbenes, including resveratrol, piceatannol and oxyresveratrol, through Perkin methodology is described. Starting from 3,5-dihydoxyacetophenone (1), the common intermediate 3,5-dimethoxyphenylacetic acid (3) can be obtained via methylation and Willgerodt-Kindler reaction. Perkin condensations between (3) and substituted phenylaldehydes 4 furnished E-2,3-diarylacrylic acids 5, followed by decarboxylation in Cu/quinoline giving stilbene intermediates 6 which bear the Z-configuration. Finally, through a simultaneous demethylation/isomerization process in AlI3/CH3CN system, the target compounds 7a-c can be obtained respectively in good to high overall yields. The synthetic method proved to be more concise, trans-specific, mild, economical and commonly applicable.
- Sun, Hong-Yi,Xiao, Chun-Fen,Cai, Yu-Chen,Chen, Yu,Wei, Wen,Liu, Xian-Ke,Lv, Ze-Liang,Zou, Yong
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experimental part
p. 1492 - 1496
(2010/12/25)
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- Syntheses of resveratrol and its hydroxylated derivatives as radical scavenger and tyrosinase inhibitor
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Eight hydroxylated stilbene derivatives including resveratrol, desoxyrhapontigenin and piceatannol as potential radical scavenger and tyrosinase inhibitor are synthesized using optimized Wittig-Horner reaction for excellent trans-selectivity in good yields. Antioxidant activity was tested against ABTS radical and tyrosinase inhibitory activity was performed with L-tyrosine as the substrate based on previous procedure with some modification. In general, catecholic stilbenes showed stronger activity against ABTS radical and resorcinolic moiety showed stronger tyrosinase inhibitory activity. Synthetic piceatannol which containing both catecholic and resorcinolic moieties showed the strongest activity in both as ABTS radical scavenger and tyrosinase inhibitor with IC50 values of 4.1 and 8.6 μM, respectively.
- Lee, Hyun Suck,Lee, Byung Won,Kim, Mi Ran,Jun, Jong-Gab
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experimental part
p. 971 - 975
(2010/10/21)
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- PROCESS FOR THE SYNTHESIS OF POLYHYDROXYSTILBENE COMPOUNDS
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The invention relates to a process for the synthesis of stilbene derivatives of formula (I)-(E) or (I)-(Z) in which R represents hydrogen or an OH group, by deprotection in the presence of an aluminium halide and of a tertiary amine of a compound of formula (II)-(E) or (II)-(Z) in which A represents hydrogen or an OR'1 group, and R1, R2, R3 and R'1 1independently represent an alkyl or aralkyl group.
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(2009/05/29)
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- Efficient total synthesis of piceatannol via (e)-selective wittig-horner reaction
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Efficient and practical total synthesis of piceatannol via (E)-selective Wittig-Horner reaction is demonstrated with six steps in overall 40% yield from a commercially available, cheap starting material, 3,5-dihydroxybenzoic acid. Wittig-Horner reaction o
- Young Han, Su,Suck Lee, Hyun,Hye Choi, Da,Woon Hwang, Jung,Mo Yang, Deok,Jun, Jong-Gab
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experimental part
p. 1425 - 1432
(2009/09/30)
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- STILBENE DERIVATIVES AND THEIR USE IN MEDICAMENTS
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The invention relates to stilbene derivatives of general formula (I), in which at least four of the substituents R1 to R6 do not represent hydrogen. The substituents are effective radical captors, anti-tumour active ingredients and s
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(2008/06/13)
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- Stereoselective synthesis of (E)-hydroxystilbenoids by ruthenium-catalyzed cross-metathesis
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An efficient and highly stereoselective synthetic procedure is reported for the construction of symmetrical and unsymmetrical (E)-polymethoxystilbene and (E)-polyhydroxystilbene derivatives. The strategy rests on a cross-metathesis reaction catalyzed by stable, well-defined (alkylidene)ruthenium complexes, in particular the second-generation Grubbs catalyst [RuCl2(=CHPh)(SIMes) (PCy3)] [SIMes = 1,3-bis(2,4,6-trimethylphenyl)imidazolidin-2- ylidene]. The metathesis of unprotected phenolic styrenes is illustrated by the synthesis of the important phytoalexins (E)-3,4′,5-trihydroxystilbene (resveratrol) and (E)-3,3′,4,5′-tetrahydroxystilbene (piceatannol). Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
- Ferre-Filmon, Karine,Delaude, Lionel,Demonceau, Albert,Noels, Alfred F.
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p. 3319 - 3325
(2007/10/03)
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- Hydroxystilbene compounds for reducing/inhibiting protein glycation
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The hydroxystilbenes are well suited for reducing or inhibiting the glycation of certain substrates, for example the proteins of nails and/or hair, advantageously to preventatively and/or curatively combat glycation-related aging of the nails/hair.
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- Convergent synthesis and preliminary biological evaluations of the stilbenolignan (+/-)-aiphanol and various congeners.
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Treatment of an equimolar mixture of stilbene 7 and cinnamyl alcohol 8 with silver carbonate in acetone-benzene afforded a ca. 2:1:2:1 mixture of the stilbenolignan (+/-)-aiphanol (1) and congeners 2-4 each of which show significant anti-angiogenic and CO
- Banwell, Martin G,Bezos, Anna,Chand, Satish,Dannhardt, Gerd,Kiefer, Werner,Nowe, Ulrike,Parish, Christopher R,Savage, G Paul,Ulbrich, Holger
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p. 2427 - 2429
(2007/10/03)
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- USE OF HYDROXYSTILBENES FOR DYEING, READY-TO-USE COMPOSITION CONTAINING THEM AND DYEING PROCESS
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The invention relates to the use of hydroxystilbenes for dyeing, to ready-to-use dye compositions comprising them, to a dyeing process using them and to a multi-compartment device containing the compositions used in the processes of the invention.
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- Evaluation of resveratrol derivatives as potential antioxidants and identification of a reaction product of resveratrol and 2,2-diphenyl-1- picryhydrazyl radical
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Resveratrol (3,4',5-trihydroxy-trans-stilbene), an antioxidant from grapes, and five other polyhydroxystilbenes were synthesized. Their antioxidative properties were evaluated in two model systems [pure lipid oxidation using the Rancimat method and 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging model.] 3,3',4,5'-Tetrahydroxystilbene, 3,3',4,5,5'- pentahydroxystilbene, and 3,4,4',5-tetrahydroxystilbene were found to be more active than resveratrol in both models. A dimer of resveratrol was identified as the major radical reaction product when resveratrol was reacted with DPPH radicals.
- Wang, Mingfu,Jin, Yi,Ho, Chi-Tang
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p. 3974 - 3977
(2007/10/03)
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- Simple synthesis of 5-substituted resorcinols: A revisited family of interesting bioactive molecules
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The reaction of 3,5-dimethoxybenzyl trimethylsilyl ether (3) with different aldehydes (n-PrCHO, n-C11H23CHO, MeCHO, PhCHO) in the presence of lithium powder and a catalytic amount of naphthalene (4 mol %) gave, after hydrolysis, the expected alcohols 4 in moderate yields. The dehydroxylation of these compounds through the corresponding mesylates 5 or directly from benzylic derivatives by catalytic hydrogenation, afforded compounds 6, which are finally demethylated to yield 5-alkyl-3,5-dihydroxyresorcinols, such as olivetol (7a), grevillol (7b), 1,3-dihydroxy-5-propylbenzene (7c), or dihydropinosilvine (7d). Dehydration of alcohol derivatives 4 followed by demethylation led to hydroxylated stilbene-type structures, such as pinosilvine (9d), resveratrol (9e), or piceatannol (9f), which in some cases can be hydrogenated to give saturated molecules such as combretastanin B-4 tetramethyl ether (6f) or chrysotobibenzyl (6g). Finally, when the naphthalene-catalyzed lithiation of compound 3 was performed in the presence of other electrophiles [Me3SiCl, t-BuCHO, CH3(CH2)4CHO, 4-Me3SiOC6H4CHO, (CH2)5CO, PhN = C = O, PhN = CHPh], the expected reaction products 12 were isolated, after hydrolysis.
- Alonso, Emma,Ramon, Diego J.,Yus, Miguel
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p. 417 - 421
(2007/10/03)
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- Synthesis and Protein-Tyrosine Kinase Inhibitory Activity of Polyhydroxylated Stilbene Analogues of Piceatannol
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A series of hydroxylated trans-stilbene related to the antileukemic natural product trans-3,3',4,5'-tetrahydroxy stilbene (piceatannol) (1) has been prepared and tested for inhibition of the lymphoid cell lineage-specific protein-tyrosine kinase p56lck, which plays an important role in lymphocyte proliferation and immune function.A number of the analogues displayed enhanced enzyme inhibitory activity relative to the natural product.Reduction of the double bond bridging the two aromatic rings and benzylation of the phenolic hydroxyl groups was found to decrease activity significantly.The most potent compounds in the series proved to be trans-3,3',5,5'-tetrahydroxystilbene, trans-3,3',5-trihydroxystilbene, and trans-3,4,4'-trihydroxystilbene.
- Thakkar, Kshitij,Geahlen, Robert L.,Cushman, Mark
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p. 2950 - 2955
(2007/10/02)
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- Studies on Rhubarb (Rhei Rhizoma). XIV. Isolation and Characterization of Stilbene Glucosides from Chinese Rhubarb
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Two major stilbene glucosides (1 and 2) have been newly isolated from Chinese rhubarb (commercial name: Gaoh, second grade), and characterized on the basis of chemical and spectroscopic evidence as piceatannol 4'-O-β-D-glucopyranoside (1) and its 6''-O-gallate (2).In addition, high-performance liquid chromatographic analysis has led to the characterization of minor components including sennoside, anthraquinones, and other stilbenes.Keywords- rhubarb; Polygonaceae; stilbene glucoside; stilbene glucoside gallate; piceatannol; chemical evaluation; HPLC
- Kashiwada, Yoshiki,Nonaka, Gen-Ichiro,Nishioka, Itsuo,Nishizawa, Makoto,Yamagishi, Takashi
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p. 1545 - 1549
(2007/10/02)
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- SYNTHESIS OF CONDENSED TANNINS. PART 18. STILBENES AS POTENT NUCLEOPHILES IN REGIO- AND STEREO-SPECIFIC CONDENSATIONS: NOVEL GUIBOURTINIDOL-STILBENES FROM GUIBOURTIA COLEOSPERMA
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(E)-3,3',4,5'-Tetrahydroxy- and 3',4,5'-trihydroxy-stilbenes function as strong nucleophiles in regio- and stereo-specific condensations with carbenium ions generated from 2,3-trans- and 2,3-cis-flavan-3,4,4',7-tetraols (leucoguibourtinidins) to generate
- Steynberg, Jan P.,Ferreira, Daneel,Roux, David G.
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p. 1705 - 1712
(2007/10/02)
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- Studies on Rhubarb (Rhei Rhizoma). VI. Isolation and Characterization of Stilbenes
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Nineteen stilbene derivatives (I-XIX), of which five are novel cis-stilbenes, have been obtained from a rhubarb of low quality (commercial name:, Imo-Daio).Based on chemical and spectroscopic evidence, these compounds have been characterized as rhapontigenin (I), rhaponticin (II), rhapontigenin 3'-O-β-D-glucopyranoside (III), rhaponticin 6''-O-gallate (IV), rhaponticin 2''-O-gallate (V), rhaponticin 2''-O-p-coumarate (VI), piceatannol (VII), piceatannol 3-O-β-D-glucopyranoside (VIII), piceatannol 3'-O-β-D-glucopyranoside (IX), piceatannol 3'-O-β-D-xylopyranoside (X), piceatannol 3-O-β-D-(6''-O-galloyl) glucopyranoside (XI), desoxyrhaponticin (XII), desoxyrhaponticin 6''-O-gallate (XIII), 3,4',5-trihydroxystilbene 4'-O-β-D-(6''-O-galloyl) glucopyranoside (XIV), cis-3,3',5-trihydroxy-4'-methoxystilbene 3-O-β-D-glucopyranoside (XV), cis-3,3',5-trihydroxy-4'-methoxystilbene 3-O-β-D-(6''-O-galloyl) glucopyranoside (XVI), cis-3,5-dihydroxy-4'-methoxystilbene 3-O-β-D-glucopyranoside (XVII), cis-3,3',5-trihydroxy-4'-methoxystilbene 3-O-β-D-(2''-O-galloyl) glucopyranoside (XVIII) and cis-3,3',5-trihydroxy-4'-methoxystilbene (XIX).Keywords - rhubarb; Polygonaceae; trans-stilbene; cis-stilbene; gallic acid ester; p-coumaric acid ester; rhaponticin; desoxyrhaponticin; piceatannol; 3,4',5-trihydroxystilbene
- Kashiwada, Yoshiki,Nonaka, Gen-ichiro,Nishioka, Itsuo
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p. 3501 - 3517
(2007/10/02)
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