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101.
Preparation of radioidinated L-α-methyl tyrosine by the oxidative radioiodination using chloramine-T (CAT) and iodogen (1,3,4,6-tetrachloro,-3α,
6α-diphenyl glycoluril) to generate electrophilic radioiodine has been carried out. The factors affecting the labeling yield
such as pH of the medium, reaction time, substrate and oxidizing agent concentrations have been investigated to optimize the
conditions for the preparation of radioiodinated L-α-methyl tyrosine in high radiochemical yields. Side product impurities
were observed at long reaction times and high oxidizing agent concentrations. Maximum radiochemical yields of 89.7±1.5% and
87.8±1.6% were obtained in case of CAT and iodogen, respectively. Separation and purification by high pressure liquid chromatography
(HPLC) resulted in radiochemically pure products. Using high specific activity123I, the SPECT brain imaging agent can be prepared. 相似文献
102.
The extraction of Co3+ from 0.1M aqueous acetate medium buffered to pH 5.3 by thenoyltrifluoroacetone (HTTA) in benzene and by 8-quinolinol (HQ) also in benzene at various temperatures has been studied. The species formed were Co(OH)2 (TTA)·(HTTA)2 and Co(Q3)·2HQ, respectively. 1,10-phenanthroline (Phen) as a base was also mixed with HTTA to form the species Co(OH)2(TTA)·(HTTA). Phen and Co(OH)2 (TTA)(HTTA)·2Phen. No synergism was observed upon the addition of Phen to HQ. 相似文献
103.
Berhal F Esseiva O Martin CH Tone H Genet JP Ayad T Ratovelomanana-Vidal V 《Organic letters》2011,13(11):2806-2809
Two new atropisomeric electron-poor chiral diphosphine ligand analogues of SYNPHOS were prepared, and their electronic properties are described. These two ligands afforded high performance for the Rh-catalyzed asymmetric 1,4-addition of arylboronic acids to α,β-unsaturated carbonyl compounds at room temperature. 相似文献
104.
Jasmine Siew Min Chia Ahmad Akira Omar Farouk Tengku Azam Shah Tengku Mohamad Mohd Roslan Sulaiman Hanis Zakaria Nurul Izzaty Hassan Enoch Kumar Perimal 《Molecules (Basel, Switzerland)》2021,26(13)
Neuropathic pain is a chronic pain condition persisting past the presence of any noxious stimulus or inflammation. Zerumbone, of the Zingiber zerumbet ginger plant, has exhibited anti-allodynic and antihyperalgesic effects in a neuropathic pain animal model, amongst other pharmacological properties. This study was conducted to further elucidate the mechanisms underlying zerumbone’s antineuropathic actions. Research on therapeutic agents involving cannabinoid (CB) and peroxisome proliferator-activated receptors (PPARs) is rising. These receptor systems have shown importance in causing a synergistic effect in suppressing nociceptive processing. Behavioural responses were assessed using the von Frey filament test (mechanical allodynia) and Hargreaves plantar test (thermal hyperalgesia), in chronic constriction injury (CCI) neuropathic pain mice. Antagonists SR141716 (CB1 receptor), SR144528 (CB2 receptor), GW6471 (PPARα receptor) and GW9662 (PPARγ receptor) were pre-administered before the zerumbone treatment. Our findings indicated the involvement of CB1, PPARα and PPARγ in zerumbone’s action against mechanical allodynia, whereas only CB1 and PPARα were involved against thermal hyperalgesia. Molecular docking studies also suggest that zerumbone has a comparable and favourable binding affinity against the respective agonist on the CB and PPAR receptors studied. This finding will contribute to advance our knowledge on zerumbone and its significance in treating neuropathic pain. 相似文献
105.
The 13C nmr assignments for captopril (1) and its disulfide mammalian metabolite (2) were made. Evidence was presented for the preferred conformations of these compounds to be in the trans forms. 相似文献
106.
Eman A. Mwafy A. A. Abd-Elmgeed A. A. Kandil I. A. Elsabbagh M. M. Elfass M. S. Gaafar 《光谱学快报》2013,46(9):646-652
Zinc oxide/high-density polyethylene nanocomposites with high-UV-shielding efficiency were reported. Zinc oxide nanoparticles were synthesized by the homogeneous precipitation method and calcination of the precursor at different temperatures. Zinc oxide/high-density polyethylene nanocomposites were subsequently prepared from high-density polyethylene and as-prepared zinc oxide nanoparticles via melt mixing process. The structural properties of the as-prepared zinc oxide nanoparticles and nanocomposites were studied in detail using X-ray diffractometer, Fourier transform infrared spectrometer, thermogravimetry, differential scanning calorimeter, ultrasonic pulse echo technique, scanning electron microscopy, and transmission electron microscope. The optical properties of the obtained nanocomposites were shown to depend on zinc oxide particle size and content. The nanocomposite containing zinc oxide nanoparticles with an average particle size of 25.22 nm after calcination at 350°C was found to have the most optimal optical properties, namely high-visible light transparency and high-UV light shielding efficiency, which are desirable for many important applications. 相似文献
107.
ABSTRACTThe increasing demand for radionuclides in nuclear medicine requires optimised production strategies. This study investigates whether any strategy is able to predict radionuclide production yields with simulations using the Monte Carlo code FLUKA. In further studies on the nuclear reaction 89Y(p,n)89Zr FLUKA results are compared with experimental data. In general, there is good agreement between both. Discrepancies typically can be explained by experimental details and problems. 相似文献
108.
Nonlinear Dynamics - In this paper, the weight of the rotor is considered in a 16-pole rotor active magnetic bearing system with constant stiffness. The equations of motion are derived to show the... 相似文献
109.
Elsayed M. Afsah Ez-el-Din M. Kandil Soha M. Abdelmageed Fatma T. Elbarhmtoushi 《Journal of heterocyclic chemistry》2020,57(1):346-354
Treatment of isoindolin-1,3-dione ( 1 ) with formalin and the appropriate amine or diamine afforded new N-Mannich bases and bis-(Mannich bases) 2 to 6 . The use of the appropriate hydrazide or dihydrazide as the amine component in the Mannich reaction with 1 led to Mannich bases and bis-(Mannich bases) incorporating a hydrazide moiety. The synthetic potential of sec-Mannich bases as precursors in synthesis of hybrid Mannich bases incorporating 1 was described. The N-alkylation of 1 with ketonic Mannich bases was investigated. 相似文献
110.
Electroencephalography/Magnetoencephalography (EEG/MEG) source localization involves the estimation of neural activity inside the brain volume that underlies the EEG/MEG measures observed at the sensor array. In this paper, we consider a Bayesian finite spatial mixture model for source reconstruction and implement Ant Colony System (ACS) optimization coupled with Iterated Conditional Modes (ICM) for computing estimates of the neural source activity. Our approach is evaluated using simulation studies and a real data application in which we implement a nonparametric bootstrap for interval estimation. We demonstrate improved performance of the ACS-ICM algorithm as compared to existing methodology for the same spatiotemporal model. 相似文献