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1.
以氢离子选择性电极为工作电极,盐酸或氢氧化钠为滴定剂,用多元校正滴定法对酒石酸美托洛尔片的含量进行了测定。探讨了盐酸或氢氧化钠测定酒石酸美托洛尔的可行性,比较了过滤和不过滤两种方法配制试液的测定结果。本法测定结果与中国药典(1995)中非水滴定法的对照偏差在1%之内;采用过滤和不过滤两种方法配制的试液测定结果之间的偏差在0.2%之内。  相似文献   

2.
A kinetic spectrophotometric method has been described for the determination of metoprolol tartrate in commercial dosage forms. The procedure is based on the reaction of the drug with 1‐chloro‐2, 4‐dinitrobenzene (CDNB) in dimethylsulfoxide (DMSO) at 100 ± 1 °C. The reaction is investigated by measuring the change in absorbance with time at 420 nm. Fixed‐time (ΔA) and equilibrium methods are chosen for obtaining the calibration curves. Both calibration curves were found to be linear over the concentration range of 5‐60 μg mL?1. The regression analysis of calibration data resulted in the linear regression equations of ΔA = ?1.608 × 10?4 + 3.96 × 10?3 C and A = 7.31 × 10?4 + 1.90 × 10?2 C for fixed time (ΔA) and equilibrium methods, respectively. The limit of detection (LOD) for fixed time and equilibrium methods are 1.16 and 0.415 μg mL?1, respectively. The method has been successfully applied to the quantitation of metoprolol tartrate in commercial dosage forms. Statistical comparison of the results shows that there is no significant difference between the proposed methods and El‐Ries's spectrophotometric method.  相似文献   

3.
用模板法合成了1个大环金属铜(II)配合物[CuLCl2]·3H2O (1)和3个大环金属镍(II)配合物[NiLCl2] (2),[NiL](ClO4)2 (3)和[NiLH2](ClO4)4 (4)(L=3,10-二乙基-1,3,5,8,10,12-六氮杂十四烷),通过X-射线衍射单晶结构分析测定了它们的晶体结构。晶体结构显示:配合物12的金属离子与大环配体的4个氮原子及大环平面轴向的2个氯离子以八面体配位方式配位;配合物34的金属离子与大环配体的4个氮原子以平面正方形配位方式配位,配合物4的侧链氮原子的质子化导致侧链结构翻转,使得其侧链与大环平面共面。  相似文献   

4.
Cu(II)-salicylate was synthesized and characterized by X-ray diffraction. The reaction mechanism of the Cu(II) complex with superoxide anion was studied by ESR spectroscopy, and its (superoxide dismutase) SOD-like activity was determined by a modified illumination method in phosphate buffer (pH = 7.8), micelle solutions and lamellar liquid crystals formed from surfactants CTAB and TX-100. X-ray diffraction indicated that the Cu(II) complex had a formula Cu2(Hsal)4EtOHH2O and a similar structure to the SOD active site. EPR spectra proved that the reaction mechanism of the Cu(II) complex catalyzing O 2 .- dismutation was the same as that of the proposed dismutation reaction catalyzed by SOD. Results obtained by the NBT method indicated that the Cu(II)-complex showed SOD-like activity, and the effect of microenvironment created by surfactants on its activity was same as on SOD activity. The order of the inhibition of NBT reduction by the Cu(II)-complex in different microenvironments was: in phosphate buffer (pH = 7.8) > in TX-100 micelle > in TX-100 liquid crystal, and in nonionic TX-100 organized assemblies > in cationic CTAB organized assemblies. These results were explained by the catalytic effect of micelles, and by the space restriction and high viscosity of organized assemblies of surfactants.  相似文献   

5.
The urea complex of copper was synthesized and its structure was established by Fourier transform infrared (FTIR), electron spin resonance (ESR) and atomic absorption spectroscopy and elemental analysis to be Cu(urea)4Cl2. The thermal behaviour of this complex has been studied by thermogravimetry and differential thermal analysis and FTIR and ESR. Thermal analysis shows that the decomposition of the complex occurs in four stages of weight loss of different intermediates followed by three endothermal effects. The complex is thermally stable up to 428 K. The ESR and FTIR behaviour of the Cu(II)-urea complex during thermolysis was studied between 428 and 633 K. The experimental results suggest that in this temperature range the complex decomposition occurred forming thermodynamically stable regions of Cu(II) which are ferromagnetically coupled.
Zusammenfassung Der Harnstoffkomplex von Kupfer wurde hergestellt, seine Zusammen-setzung ergab sich anhand von FTIR-, ESR- und Atomabsorptionsspektroskopie-Untersuchungen sowie Elementaranalyse mit der Formel Cu(Harnstoff)4Cl2.Mittels TG, DTA, FTIR und ESR wurde auch das thermische Verhalten dieser Komplexe untersucht. Die Thermoanalyse zeigte, daß der Zersetzungsprozeß über verschiedene Zwischen-produkte in vier Stufen mit Massenverlust verläuft, gefolgt von insgesamt drei endothermen Effekten. Bis 428 K ist der Komplex thermisch stabil. Das ESR- und FTIR-Verhalten des Cu(II)-harnstoffkomplexes bei der Thermolyse wurde im Temperaturbereich 428–633 K untersucht. Die experimentellen Ergebnisse lassen darauf schließen, daß bei der Zersetzung des Komplexes in diesem Temperaturbereich thermodynamisch stabile Regionen von ferromagnetisch gekoppeltem Cu(II) gebildet werden.
  相似文献   

6.
The reactions of N-arylthiopicolinamides (HL) with copper(II) and nickel(II) ions in organic and aqueous-organic solutions were studied. On addition of HCl, the transformation of ML2 complexes into M(HL)Cl2 occurs, while the reverse reaction takes place under the action of amphoteric protic solvents. The structures of the isolated complexes were established by IR and UV spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1546–1550, September, 1993.  相似文献   

7.
A copper complex having quinoline moiety as fluorophore has been synthesized. The anion recognition behavior of the receptor and its copper complex has been studied in acetonitrile and in acetonitrile: H2O (95:5 v/v). The copper complex shows high selectivity toward acetate over other anions studied such as F, Cl, Br, I, OAc, dl-malate, l-mandelate, benzoate, isophthalate, , and .  相似文献   

8.
瞿志荣  熊仁根 《中国化学》2008,26(2):239-242
在加热条件下,手性相转移催化剂氯化- N -(4-乙烯基苄基)辛可尼定(L1)与氯化铜在2-丁醇中反应,可得到一个单一手性的二价铜单分子配合物 N -(4-乙烯基苄基)辛可尼定三氯化铜(1)。配合物(1)和配体(L1)都可用于催化 N -(二苯基亚甲基)氨基乙酸叔丁基酯(3)烷基化反应,催化结果表明:使用配合物N-(4-乙烯基苄基)辛可尼定三氯化铜的反应对映体选择性比使用配体的更高,配合物催化能力的提高可能与配合物中喹啉环的N原子与铜配位、分子刚性增加有关。  相似文献   

9.
Two macrocyclic Schiff base ligands, L1 [1+1] and L2 [2+2], have been obtained in a one-pot cyclocondensation of 1,4-bis(2-formylphenyl)piperazine and 1,3-diaminopropane. Unfortunately, because of the low solubility of both ligands, their separation was unsuccessful. In the direct reaction of these mixed ligands (L1 and L2) and the appropriate metal ions only [CoL1(NO3)]ClO4, [NiL1](ClO4)2, [CuL1](ClO4)2 and [ZnL1(NO3)]ClO4 complexes have been isolated. All the complexes were characterized by elemental analyses, IR, FAB-MS, conductivity measurements and in the case of the [ZnL1(NO3)]ClO4 complex with NMR spectroscopy.  相似文献   

10.
1 INTRODUCTION The polypyridine ligands, such as 2,2-bipyri- dine and 1,10-phenanthroline, continue to attract much research interest, mainly because of their rich redox chemistry and photochemistry[1, 2]. Most work on phenanthroline derivatives has bee…  相似文献   

11.
Co(II), Ni(II) and Cu(II) complexes were synthesized with thiosemicarbazone (L(1)) and semicarbazone (L(2)) derived from 2-acetyl furan. These complexes were characterized by elemental analysis, molar conductance, magnetic moment, mass, IR, electronic and EPR spectral studies. The molar conductance measurement of the complexes in DMSO corresponds to non-electrolytic nature. All the complexes are of high-spin type. On the basis of different spectral studies six coordinated geometry may be assigned for all the complexes except Co(L)(2)(SO(4)) and Cu(L)(2)(SO(4)) [where L=L(1) and L(2)] which are of five coordinated square pyramidal geometry.  相似文献   

12.
合成并通过单晶衍射、元素分析及红外光谱表征了配合物[Cu4(L)2(CH3O)2(CH3OH)4(SO42]SO4·6CH3OH(1)的结构(L为3-乙基-2-乙酰吡嗪双缩水合肼)。单晶衍射结果表明,在配合物1中,每个Cu(II)离子与来自半个腙配体的2个N原子和分别来自配位甲醇、桥联甲氧基及2个不同硫酸根的单齿配位和桥联氧原子配位,形成扭曲的八面体配位构型。4个Cu(II)离子通过对称操作形成理想的平面四核铜簇。此外,荧光光谱表明配合物1与DNA的相互作用强于配体L。  相似文献   

13.
《Analytical letters》2012,45(15):1905-1913
Abstract

The neutral [Cu(II) - streptomycin .4 H2O] complex is prepared and characterized by elemental analysis, TGA, IR, electronic and ESR spectra. The bonding between Cu(II) and streptomycin is found to take place through a Cu-O bond. The indirect estimation of streptomycin sulfate by atomic absorption spectroscopy is affected by the addition of an excess of cupric ions in slightly alkaline medium; the unreacted copper is separated as insoluble carbonate. The concentration of streptomycin in its product with copper is then indirectly determined from a pre-drawn caliberation curve for standard copper sulfate solutions.  相似文献   

14.
Bis(N-alkyldithiocarbamato)nickel(II) complexes (1–5) [Ni(S2CNHR)2] (where R?=?Me, Et, n-Pr, i-Pr, n-Bu) were synthesized by the reaction of NiCl2?·?6H2O and the corresponding sodium salt of N-alkyldithiocarbamate in 1?:?2 molar ratio in aqueous medium. These bis(N-alkyldithiocarbamato)nickel(II) complexes (1–5) were characterized by elemental analysis, UV-Visible, IR, and 1H/13C-NMR spectroscopy. The crystallographic investigation of [Ni(S2CNH(n-Pr))2] (3) and [Ni(S2CNH(i-Pr))2] (4) revealed distorted square-planar geometry around nickel(II). The dithiocarbamates have anisobidentate coordination with nickel and the dithiocarbamates are trans.  相似文献   

15.
A Cu(II) coordination polymer (CP) (that is, [Cu2(OH)(H2O)2(cbca)·2H2O]n (1)) has been obtained with the reaction between Cu(II) salt and 4′-(1-carboxyethoxy)-[1,1′-biphenyl]-3,5-dicarboxylic acid (H3cbca), a semi-rigid tricarboxylic acid ligand under the hydrothermal reaction condition. Prevention activity of the new compound on hypotension after anesthesia surgery was evaluated and the related mechanism was researched at the same time. The noninvasive blood pressure monitor was firstly conducted to measure the blood pressure of the animal after compound treatment. Besides, the real time RT-PCR assay was also used to determine theα receptor relative expression on vascular endothelial cells after compound treatment.  相似文献   

16.
A new dinuclear copper complex, [Cu(C13H9N2O)Cl]2·(CH3CN)2 (C30H24Cl2Cu2N6O2), has been synthesized and characterized by X-ray structure determination. It crystallizes in the tricli- nic system, space group P1, with a = 7.6677(14), b = 9.2375(17), c = 11.227(2) , α = 81.338(3), β = 88.173(4), γ = 66.199(3)o, V = 718.9(2) 3, Z = 1, Mr = 698.53, F(000) = 354, Dc = 1.613 g/cm3, μ(MoKα) = 1.705 mm-1, the final R = 0.0645 and wR = 0.1364 for 2474 unique reflections with 1809 observed ones (I > 2σ(I)). In the title complex, each copper(II) atom is located at the center of a distorted tetrahedron consisting of four coordinate atoms (one nitrogen atom, two oxygen anions, and one chlorine atom). Two copper(II) atoms are bridged by two oxygen anions (O(1) and O(1a)) of two phenolates to form a Cu(II)–Cu(II) binuclear entity, and the distance between two copper(II) atoms is 3.0144(15) .  相似文献   

17.
Four new heterotrinuclear complexes have been synthesized and characterized, namely {[Ni(L)2]2[Cu(opba)]}(ClO4)2, where opba denotes o-phenylenebis(oxamato) and L stands for 1,10-phenanthroline(phen) (1), 5-nitro-l,10-phenanthroline(NO2-phen) (2), 2,2′-bipyridyl(bpy) (S) and 4,4′-dimethyl-2,2′-bipyridyl(Me2bpy) (4). The temperature dependence of the magnetic susceptibility of {[Ni(phen)2]2[Cu(opba)]}(ClO4)23H2O has been studied in the 4–300 K range, giving the exchange integral J—109 cm?1. The HMT vs. T plot exhibits a minimum at about 100 K, characteristic of this kind of coupled polymetallic complex with an irregular spin-state structure.  相似文献   

18.
1 INTRODUCTION There has been increasing interest of Cu(II) and phenanthroline complexes in the field of coor- dination chemistry[1~4]. At the same time, nitronyl nitroxide radicals have played a prominent role in the design and construction of molecula…  相似文献   

19.
New Ni (II) and Cu (II) complexes with pyridoxal-semicarbazone were synthesized and their structures were solved by X-ray crystallography. This analysis showed the bis-ligand octahedral structure of [Ni(PLSC-H)2]·H2O and the dimer octahedral structure of [Cu(PLSC)(SO4)(H2O)]2·2H2O. Hirshfeld surface analysis was employed to determine the most important intermolecular interactions in the crystallographic structures. The structures of both complexes were further examined using density functional theory and natural bond orbital analysis. The photocatalytic decomposition of methylene blue in the presence of both compounds was investigated. Both compounds were active toward E. coli and S. aureus, with a minimum inhibition concentration similar to that of chloramphenicol. The obtained complexes led to the formation of free radical species, as was demonstrated in an experiment with dichlorofluorescein-diacetate. It is postulated that this is the mechanistic pathway of the antibacterial and photocatalytic activities. Cyclic voltammograms of the compounds showed the peaks of the reduction of metal ions. A molecular docking study showed that the Ni(II) complex exhibited promising activity towards Janus kinase (JAK), as a potential therapy for inflammatory diseases, cancers, and immunologic disorders.  相似文献   

20.
Poly(propylene imine) dendrimers having 8, 32, and 64 primary amine end groups form diamino Cu(II), diamino Zn(II), and tetramino Co(III) complexes that are identified spectrophotometrically and titrimetrically. The dendrimer–metal ion complexes catalyze the hydrolysis of p-nitrophenyl diphenyl phosphate in zwitterionic buffer solutions at pH ≤ 8.1 with relative activities Cu(II) > Zn(II) > Co(III). The rates of hydrolysis are faster with sodium perchlorate than with sodium chloride to control ionic strength. In sodium perchlorate solutions with Cu(II) the rates increase with increasing size of the dendrimer. In sodium chloride solutions with Cu(II) the rates decrease with increasing size of the dendrimer. Rate constants in buffered sodium chloride solutions of dendrimers and 1.0mM Cu(II) are 1.3–6.3 times faster than in the absence of Cu(II). The fastest hydrolyses occurred at a dendrimer primary amine to Cu(II) ratio NH2/Cu ≤ 2. At NH2/Cu = 4 and with the 1,4,7,10-tetraazacyclodecane complex of Cu(II) hydrolysis rates were much slower. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2727–2736, 1999  相似文献   

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