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991.
992.
《Journal of Coordination Chemistry》2012,65(10):1089-1099
Aquabis(N,N-dimethylglycinato)copper(II) dihydrate, [Cu(dmg)2(H2O)]·2H2O, has been synthesized and characterized by elemental analysis, FT-IR, magnetic data, thermal analysis, solution UV-visible spectroscopy, X-ray crystal structure analysis and electrospray ionization mass spectroscopy. The square pyramidal copper(II) complex crystallizes in the orthorhombic space group P212121. The complex cleaves circular plasmid DNA (pBR322) in the presence of H2O2. The extent of cleavage varies with the concentration range of the complex, the type of buffer used, pH of buffer and the concentration of H2O2. Hydroxyl radical scavenger can inhibit the nucleolytic ability of this complex. 相似文献
993.
《Journal of Coordination Chemistry》2012,65(24):4290-4298
The selective extraction of Au(III) in the presence of Zn(II) by salting-out of 2-propanol was investigated. The salting-out effect increased partitioning between water and 2-propanol in the presence of sodium chloride in aqueous–organic mixtures. This is observed through the distribution coefficient, which increases with salt addition. First-derivative spectrophotometry, which eliminates interference from overlapping spectral bands, was used for the determination of trace Au(III) in the presence of Zn(II). Absorption spectra were recorded and the first-derivative spectra were obtained using Δλ?=?10?nm. The calibration graph was linear for 0.857–5.142?µg?mL?1 and the detection limit was 0.038–8?µg?mL?1. The proposed method has been successfully applied to the determination of trace Au(III) in synthetic mixtures and Algerian low gold ore solutions. The results agree with those obtained by atomic absorption spectroscopy and the recoveries were >98%. The relative standard deviations were in all instances less than 3%. 相似文献
994.
《Journal of Coordination Chemistry》2012,65(16):1477-1483
Synthesis and characterization of a new Pt(II)–mimosine complex are described. Elemental, mass spectrometry and thermal analyses for the complex are consistent with the formula [PtCl2(C8H10N2O4)]·1.5H2O. 13C NMR, 15N NMR and infrared spectroscopy indicate coordination of the ligand to Pt(II) through the N and O atoms in a square-planar geometry. The final residue after thermal treatment was identified as metallic Pt. The complex is soluble in dimethylsulfoxide. 相似文献
995.
《Journal of Coordination Chemistry》2012,65(3):339-346
New water-soluble zinc(II) Schiff-base complexes derived from amino acids (glycine, L-phenylalanine, and L-valine) and salicylaldehyde-5-sulfonates (sodium salicylaldehyde-5-sulfonate and sodium 3-methoxy-salicylaldehyde-5-sulfonate) have been synthesized. The complexes were characterized by elemental analysis, IR, electronic, 1H?NMR, and 13C?NMR spectra. In the IR spectra of the complexes, the large difference between the asymmetric νas(COO) and symmetric νs(COO) carboxylate stretch, Δν(νas(COO)–νs(COO)) of 199–247?cm?1, indicates monodentate coordination of the carboxylate group. Spectral data showed that in these complexes the ligand is a tridentate ONO moiety, coordinating to the metal through its phenolic oxygen, imine nitrogen, and carboxyl oxygen. 相似文献
996.
Dajiang Mei Wenlong Yin Kai Feng Lei Bai Zheshuai Lin Jiyong Yao Yicheng Wu 《ChemInform》2012,43(16):no-no
The new title compound is prepared from a mixture of AgGaSe2 (obtained from the elements at 900 °C, 2 d) and CsI in the molar ratio 1:2 (silica tube, Ar, 800 °C, 48 h). 相似文献
997.
Novel chiral receptors based on l-phenylalanine and l-valine have been synthesized and their chiral recognition properties toward mandelic acid and N-tosyl α-amino acids are studied. The phenylalanine-based receptor undergoes enantioselective gel formation with R-mandelic acid and N-tosyl-d-valine, whereas the valine-linked receptor in their presence results in the formation of precipitates. 相似文献
998.
Silvia RoscalesÁngela Rincón Eduardo BuxaderasAurelio G. Csákÿ 《Tetrahedron letters》2012,53(35):4721-4724
The conjugate addition of boronic acids to α,β-unsaturated ketones catalyzed by acylating reagents has been explored. The results show that trifluoroacetic anhydride catalyzes the addition of vinylboronic acids under experimentally simple and metal-free conditions for a variety of substrates with good yields. 相似文献
999.
《Analytical letters》2012,45(5):865-881
Abstract It was found that gmanylic acid (GMP) can be selectively completed with Tb3+ at pH 6.0-6.6, which then emits strong fluorescence characteristic of Tb3+. This reaction can be used for the determination of GMP in presence of adenylic acid (AMP), uridylic acid (UMP) and cylidylic acid (CMP). A linear relationship is obtained between the fluorescence intensity and GMP concentration in the range of 2.0×10?7 - 1.0×10?4M. The detection limit is 2.0×10?8 M. The results showed that the composition ratio and apparent stability constant of GMP-Tb complex were 1:1 for GMP Tb3+- and 2.3×10?5, respectively. 相似文献
1000.
《Analytical letters》2012,45(13):1099-1109
Abstract A comparison of liquid chromatography with electrochemical detection (LCEC) and gas chromatography mass spectrometry (GCMS) has been made for analysis of homovanillic acid (HVA) in rat brain tissue. The LCEC procedure gave slightly higher average values of HVA in the samples measured; however, the HVA content determined by both methods related significantly. Rat brain meostriatum was used as representative samples for comparison of the two analytical procedures. 相似文献