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An improved synthesis of the anti-cancer agent DMU-212 (trans-3,4,5,4′-tetramethoxystilbene) is described. The methodology involves the use of a Pd-oxazoline catalyst as a mediator of a regio-selective (Heck) C-C bond formation reaction. A simple isolation step is then used to obtain the title material. The compound has been further characterised in the solid-state by X-ray diffraction methods. 相似文献
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A reversed-phase liquid chromatographic method, optimised for the separation of trans-, and cis-resveratrol, catechin, epicatechin, quercetin and rutin, is reported. Separation was achieved using a C18 column and a gradient
elution with acetonitrile and 5% formic acid aqueous solution. The analyses required an equilibration period of 10 min and
a run time of 25 min for completion. Identification was based on retention characteristics and by relative UV spectra, obtained
by photodiode array detector and were compared with commercial standards. Analyses were performed without any sample pre-treatment.
Detection was carried out by UV–Vis detector at three different wavelengths. The detection limit ranged from 0.16 μgm L−1 (cis-resveratrol) to 1.5 μgm L−1 (+)-catechin. Investigation was extended to quantitative determination of phenol compounds in Italian red wine and to investigate
the stability of the six antioxidants. 相似文献
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AbstractThe study on inhibitory effects of resveratrol glucosides (REs) on advanced glycation endproducts (AGEs) formation is still unmet. Herein, for the first time, the antiglycation activities of five REs in the fetal bovine serum proteins (FBS)/fructose system were evaluated, and its structure-activity relationship and antiglycation mechanism were further explored. These REs showed remarkable inhibition toward AGEs formation. Among them, Piceatannol-3'-O-glucoside (PG) exhibited highest antiglycation activity as reflected in approximately 80% inhibition of fluorescent AGEs at the concentration of 1.0?mM. The structure-activity relationship analysis indicated that glucoside attached to the B ring of resveratrol displays a superior antiglycation activity. Moreover, the results of antiglycation mechanism showed that the antiglycation activity of REs was proportional to their antioxidant capacity and methylglyoxal (MGO) trapping capacity. Therefore, the REs are promising candidates worthy of further exploration for preventing AGEs accumulation in vivo, thereby treating AGEs-associated diseases. 相似文献
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The adsorptive voltammetric behavior of resveratrol was studied at a graphite electrode in B‐R buffer (pH = 6.0) solution using adsorptive cyclic voltammetric technique. The oxidation of resveratrol is an irreversible adsorption controlled process. The oxidation mechanism was proposed and discussed in this work. The dependence of the current on pH and the concentration and nature of buffer were investigated to optimize the experimental conditions for the determination of resveratrol. It was found that in the range of 8.0 × 10?9 ~ 2.0 × 10?6 mol/L, the currents measured by differential pulse voltammetries presented a good linear property as a function of the concentrations of resveratrol. In addition, validation parameters, such as reproducibility, sensitivity and recovery were evaluated as well. The proposed method was also successfully applied for the determination of resveratrol in Chinese patent medicine with good results. 相似文献
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定量核磁共振波谱法同时测定中药虎杖中白藜芦醇和虎杖苷的含量 总被引:2,自引:0,他引:2
建立了定量核磁共振波谱法同时测定虎杖中白藜芦醇和虎杖苷的方法。样品用80%乙醇和丙酮两次超声提取净化,再用定量核磁共振波谱法测定。考察了样品预处理和核磁共振实验条件对测定结果的影响,选择氘代二甲亚砜-重水(10∶1,V/V)为溶剂,用基准物质邻苯二甲酸氢钾标定的2,3,5-三碘苯甲酸为内标,选择脉冲延迟时间为5 s,采样次数为32次。定量峰为6.388~6.391(白藜芦醇:H-2,6,d,2H)和6.322~6.330(虎杖苷:H-4,t,1H)。结果表明,NMR测定的精密度均小于0.6%,线性相关系数(r)均大于0.999,白藜芦醇和虎杖苷的检出限分别为0.23和0.24 g/L,定量限分别为0.69和1.57 g/L,包括样品提取过程的回收率分别为97.7%~103.5%(RSD=2.4%)和94.5%~99.2%(RSD=1.6%),显示出定量核磁共振法在中药定量时的可靠性。实际测定4种虎杖饮片及配方颗粒样品中白藜芦醇和虎杖苷含量分别为3.57~5.69 mg/g和12.73~24.07 mg/g。 相似文献
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Several 8-8-coupled tetraarylfuran-type oligostilbenes were prepared through FeCl3·6H2O-catalyzed regioselective oxidative couplings of protected resveratrol precursors. The global deprotection of the coupling dimers in a one-pot reaction yielded (±)-pallidol instead of the targets (±)-restrytisol B and (±)-tricuspidatol A. 相似文献
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密闭系统中微波辅助萃取机制探讨 总被引:9,自引:2,他引:9
通过与普通加热萃取虎杖中白藜芦醇的产率进行对比 ,对密闭系统中微波辅助萃取的机理进行了探讨。结果表明 ,微波辅助萃取与普通加热萃取二者的活化能相差不大 ,分别为30.06和30.32kJ·mol-1。但微波辅助萃取的表观速率常数约是普通加热萃取的20倍。并且还利用电子扫描显微镜对样品微结构进行了观察 ,研究表明 ,细胞内极性成分如水吸收了微波能后压力迅速增加导致细胞结构的破坏是MAE快速高效的关键 ,由于细胞的破坏 ,萃取剂和萃取目标化合物更容易通过细胞壁 ,加速了扩散速度 ,进而加速了萃取速度。 相似文献
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《Analytical letters》2012,45(4):557-569
In this study, we established a rapid, sensitive, and specific liquid chromatography method coupled with electrospray ionization–tandem mass spectrometry to evaluate the disposition of resveratrol and its metabolites in rat tissues following oral administration. Here, we validate this method and show that it is useful for quantifying tissue concentrations of resveratrol and its metabolites with acceptable specificity, linearity, lower limits of quantification, precision, accuracy, and recovery. The present study demonstrates that the major distribution of the trans-resveratrol and its metabolites in investigated tissues, which suggests that there is a specified range of target organs for cancer chemoprevention by polyphenols. 相似文献
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