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91.
Terpenoid-like bischalcones (3 and 4) were synthesized from the reaction of α- and β-ionones and benzaldehydes in excellent yields. The Michael addition of 1,3-dicarbonyl compounds to bischalcones (3 and 4) resulted in the formation of cyclohexenones derivatives (10a–d and 14a, b) via regioselective addition of 1,3-dicarbonyls and then cyclization. 相似文献
92.
93.
Nair VA Mustafa SM Mohler ML Fisher SJ Dalton JT Miller DD 《Tetrahedron letters》2004,45(51):9475-9477
A series of optically active nonsteroidal selective androgen receptor modulators with structures analogous to bicalutamide was prepared by replacing the trifluoromethyl group with iodine and the sulfonyl linker by oxygen. 相似文献
94.
A highly sensitive ultra high pressure liquid chromatography (UHPLC‐MSMS) method for estimation of ropinirole in rat brain homogenate and plasma has been validated. The method was successfully used for the degradation kinetics in different stress condition and regulated temperature. The chromatographic separation was achieved using isocratic mobile phase, consisting of acetonitrile–2mM ammoniumacetate (28:72 v/v; 0.25 mL min?1). The mass spectrometer was operated in synapt mass spectrometry mode via positive electrospray ionization using the transitions m/z 260 → m/z 261 for ropinirole, and m/z 324.39 → m/z 262.161 as a parent ion of escitalopram (IS). The assay for ropinirole was linear over the range of 0.5–100 ng mL?1 (r2; 0.999). The intra‐ and inter day precisions were less than 11.2% in terms of relative standard deviation (R.S.D.), and the accuracy was within ±6.4% in terms of relative error (RE). The mean extraction‐efficiency of QC samples (MQC, 8 ng/mL) was ≥80%. The lower limit of quantification (LLOQ) was 0.049 ng/mL where as lower limit of detection (LLOD) was 0.016 ng/mL. All the peaks of degradation were well resolved. The degradation kinetics of ropinirole, showed highest stability (t1/2 256.66/h; t0.9, 39.11/h) in acidic medium, lower stability in alkaline environment (t1/2, 103.43/h; t0.9, 15.76/h) and highly susceptible in oxidative environment (t1/2, 21.58/h; t0.9, 3.28/h). The applicability of this assay was demonstrated and successfully applied for pharmacokinetic profiling of ropinirole in Wister rat brain homogenate after intranasal administration. 相似文献
95.
Abdurrahmanoğlu S Ozkaya AR Bulut M Bekaroğlu O 《Dalton transactions (Cambridge, England : 2003)》2004,(23):4022-4029
A new sandwich-tpype dilutetium tetraphthalocyanine 4 has been synthesized by the reaction of dimeric lutetium(III) phthalocyanine 3 with two equiv. of dilithium octakishexylthiophthalocyanine in amyl alcohol. Compound 3 was prepared from 4',5',4",5"-tetraiminoisoindoline(1,4,7,10-tetrathia-12-crown-4) 1, 4,5-bis(hexylthio)-1,2-diiminoisoindoline and lutetium acetate in amyl alcohol. Compounds 3 and 4 were characterized by elemental analysis, UV/visible, IR, (1)H NMR and ESR spectroscopy. The electrochemical and electrochromic properties of 3 and 4 have been examined by cyclic voltammetry. Both 3 and 4 displayed well-defined electrochromic behavior. 相似文献
96.
3-Alkyl(Aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) reacted with 2-furoyl chloride and thiophene-2-carbonyl chloride to afford the corresponding 3- alkyl(aryl)-4-(2-furoylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (3) and 3-alkyl(aryl)- 4-(2-thienylcarbonylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (4), respectively. The new compounds synthesized were characterized by using IR, 1H-NMR, 13C-NMR and UV spectral data together with elemental analysis. In addition, to investigate the effects of solvents and molecular structure upon acidity, compounds 3 and 4 were titrated potentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents (isopropyl alcohol, tert-butyl alcohol, N,N-dimethylformamide and acetonitrile). The half-neutralization potential values and the corresponding pKa values were determined for all cases. 相似文献
97.
The divalent metal ion sorption (Cu(2+), Cd(2+), Ni(2+), and Pb(2+)) on chromium phosphate (CrPO(4)) was studied as a function of pH, temperature, and concentration of metal ions. The sorption of metal ions is observed to increase with the increase in pH, temperature, and concentration of metal ions in solution. The mechanism of sorption is found to be the exchange of the hydrolyzed metal cations with the protons from solid at high temperature. The sorption at low temperature is found to be accompanied by the precipitation of the corresponding metal phosphates such as Pb(3)(PO(4))(2). 相似文献
98.
Mustafa Aghazadeh Abbas-Ali Malek Barmi Hamid Mohammad Shiri 《Russian Journal of Electrochemistry》2013,49(4):344-353
Nanoparticles, nanospheres and nanorods of Y(OH)3 and Y2O3 were prepared via cathodic electrodeposition from chloride bath through applying different current densities. First, yttrium hydroxide precursors were cathodically grown on the cathode surface at the current densities of 2, 1, 0.5, 0.25 and 0.1 mA cm?2. Then hydroxide powders were heat-treated at 600°C for 3 h. The composition, crystal structure and morphology of the prepared oxide and hydroxide products were investigated by means of differential scanning calorimetery (DSC), X-ray diffraction (XRD), scanning and transmission electron microscopes (SEM and TEM) and FT-IR spectroscopy. Mechanism of base electrogeneration at the applied conditions, and intercalation of chloride ions in the deposit structure during the electrodeposition were proposed and confirmed by the XRD and TG analyses. The results showed that the structural and morphological properties of the products are directly dictated by the applied current density and it can be recognized as the main factor affecting on the cathodic electrodeposition of Y2O3. 相似文献
99.
In this study, synthesis, characterization and electrorheological (ER) properties of polyindene (PIN) and polyindene/kaolinite composites were carried out by cationic radical polymerization using FeCl3 as the oxidizing agent. The homopolymer and composites, containing different amounts of PIN were characterized by FTIR spectroscopy, thermo‐gravimetric (TGA) analyses, scanning electron microscopy (SEM) and dynamic light scattering (DLS) methods. The conductivity and dielectric properties of PIN and PIN/kaolinite composites were determined. Suspensions of PIN and PIN/kaolinite composites were prepared in silicone oil (SO), at a series of concentrations (c=5–25 m/m %). The effects of concentration, shear rate, electric field strength, frequency, temperature and promoter on ER activities of suspensions were investigated. 相似文献
100.
Acrylamide based monomer, 5-methyl-2-thiozyl methacrylamide (MTMAAm) was synthesized by the reaction of 2-Amino-5-methyl thiazole with methacryloyl chloride in the presence of triethylamine(NR3) at 0–5°C. The monomer MTMAAm was characterized by FT-IR and 1H-and 13C-NMR spectral studies. A new chelating resin, poly(5-methyl-2-thiozyl methacrylamide-co-2-acrylamido-2-methyl-1-propanesulfonic acid-co-divinylbenzene) [MTMAAm/AMPS/DVB] was synthesized. This resin was characterized by FT-IR. In order to determine the adsorption behavior of chelating resin, the adsorption isotherm of Cr(III) and Cu(II) were studied. It was found that the adsorption isotherm of the ions fitted with Langmuir-type isotherms. From the Langmuir equation, the adsorption capacity of chelating resin for Cr(III) and Cu(II) was found to be 7.77 mg g? 1 and 4.27 mg g? 1, respectively. Binding equilibrium constant was calculated to be 0.155 L mg? 1 and 0.106 L mg? 1 for Cu(II) and Cr(III), respectively. 相似文献