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1.
在25±0.1℃,I=0.1mol·dm-3KNO3条件下,80%(v/v)DMSO-H2O混合溶剂中,应用pH法测定了甘氨酸,L一缬氨酸,L-异亮氨酸,L-脯氨酸,L-丝氨酸,DL-苯丙氨酸等六种α-氨基酸(缩写为α-AA,记为B配体)的酸离解常数,铜(Ⅱ)-α-氨基酸。锌(Ⅱ)-α-氨基酸二元配合物的稳定常数及铜(Ⅱ)-芬布芬-α-氨基酸(芬布芬缩写为Fen,记为A配体)和锌(Ⅱ)-芬布芬-α-氨基酸三元配合物的稳定常数。实验发现,在下面三对参数之间,即logβ102与pK2B,lOgβ111;与pK2B及10gβ111与logβ102,均存在良好的直线自由能关系。用△logKM和△logβ111两个参量描述了三元配合物相对于母体二元配合物的稳定性。讨论了溶剂的性质,配合物分子内配体之间的疏水作用,芳环之间的堆积作用对配合物稳定性的影响。  相似文献   

2.
合成了一种缩氨基硫脲Ni(Ⅱ)配合物[Ni(QCMT)2]Cl2·2CH3OH·1.5H2O(QCMT为喹啉-2-甲醛-N4-甲基缩氨基硫脲)。该配合物晶体属于三斜晶系,P1空间群,a=1.0002(2)nm,b=1.0939(2)nm,c=1.5836(3)nm,α=93.99(3)°,β=105.25(3)°,γ=108.46(3)°。中心离子Ni2+处于变形八面体配位环境中。电子吸收光谱、荧光光谱及圆二色谱分析表明该配合物通过静电作用方式与DNA相结合。测定了该Ni(Ⅱ)配合物与配体(QCMT)对人乳腺癌细胞系MCF-7、人卵巢癌细胞系SKOV-3及人非小细胞肺癌耐顺铂细胞系A-549/CDDP的体外细胞毒活性。结果表明,Ni(Ⅱ)配合物对MCF-7细胞系的细胞毒活性强于顺铂,同时该配合物对MCF-7和SKOV-3两种细胞系的细胞毒活性明显优于其配体。  相似文献   

3.
在25±0.1℃,I=0.1mol·dm-3KNO3条件下,应用pH法测定了水杨醛缩α-氨基酸 的酸离解常数及它们与Mn(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Zn(Ⅱ)生成的二元配合物的稳定常数.结果表明,对于同一种配体,配合物的稳定性均符合金属离子的欧文-威廉序;对于同一种金属离子,在配合物稳定性与配体的碱性之间均存在良好的直线自由能关系.  相似文献   

4.
聂雪  陈满生  庾江喜 《无机化学学报》2013,29(12):2704-2708
以3,5-二硝基苯甲酸,咪唑为配体,合成了新化合物[Cd(H2O)2(DNBA)(Im)2](DNBA)·H2O,(DNBA=3,5-二硝基苯甲酸阴离子)。该配合物属正交晶系,空间群为Ccc2,晶胞参数:a=1.324 99(4) nm,b=1.516 01(5) nm,c=2.789 22(8) nm;V=5.602 7(3) nm3,Dc=1.719 g·cm-3,Z=8,μ=0.866 mm-1,F(000)=2 912,最终偏离因子R1=0.058 3,wR2=0.146 4。该配合物中包含两个单核镉(Ⅱ)配合物,且配合物中还包含未配位的3,5-二硝基苯甲酸,金属中心均是六配位变形八面体结构。并测定和研究了标题化合物的热重和荧光性能。  相似文献   

5.
以2,2′-联吡啶(L1)为基础,合成了5,5′-二溴-2,2′-联吡啶(L2),5-咔唑-5′-溴-2,2′-联吡啶(L3),5,5′-二咔唑-2,2′-联吡啶(L4)3个N,N-双齿配体,然后以二苯甲酰甲烷(DBM)作为第一配体合成了这4种配体相应的铕配合物。在387 nm激发条件下,配合物都表现出非常强的铕离子5D0-7FJ (J=0,1,2,3,4)的特征发射。引入咔唑基团后,不仅扩大了配合物吸收光能的范围、增强了配合物的吸收强度,而且提高了配合物的光致发光性能。  相似文献   

6.
L-苏糖酸与金属离子的配位性能   总被引:9,自引:0,他引:9  
本文在298K、I=0.1 mol·L-1 KNO3条件下测定了L-苏糖酸的质子化常数及其与钙(Ⅱ)、镉(Ⅱ)、锌(Ⅱ)、钴(Ⅱ)、铜(Ⅱ)二元配合物的生成常数。L-苏糖酸的质子化常数与葡萄糖酸的质子化常数一致,pKa为3.56。其与金属离子的配位方式也与葡萄糖酸一致,但其二元配合物的生成常数明显比葡萄糖酸大。L-苏糖酸与不同金属离子作用的方式不同,与钙(Ⅱ)、镉(Ⅱ)、锌(Ⅱ)、钴(Ⅱ)配位时不解离出醇羟基质子,而与铜(Ⅱ)配位时则  相似文献   

7.
合成并通过单晶衍射、元素分析及红外光谱表征了配合物[Ni(L12]·2DMF (1),[Cu(L12]·THF·0.25MeOH·2.25H2O(2), [Ni(L22]·2MeOH(3)和[Cu(L22]·2EtOH (4)的结构(HL1:5-甲酰基-3,4-二甲基-吡咯-2-甲酸乙酯缩硫代氨基脲,HL2:5-甲酰基-2,4-二甲基-吡咯-3-甲酸乙酯缩4-异丙基氨基硫脲)。单晶衍射结果表明,除溶剂分子不同外,配合物1~4的结构相似。每个配合物的中心金属离子分别与来自2个阴离子L-配体的N2S2电子供体配位,采取扭曲的平面正方形配位构型。荧光光谱结果表明,配合物与DNA的相互作用强于其配体。  相似文献   

8.
合成了Schiff碱配体3-乙酰吡啶缩邻氨基苯甲酰腙(L1)及4-乙酰吡啶缩邻氨基苯甲酰腙(L2),并分别与HgCl2进行了配位反应,得到2个配位聚合物{[Hg(L1)Cl2]·CH3OH}n (1)和[Hg(L2)Cl2]n (2),采用1H NMR、FTIR和元素分析等手段对化合物进行了表征,并对配合物的热稳定性进行了考察。通过X射线单晶体衍射技术测定了2个配合物的单晶结构,结构解析表明,配合物1属于三斜晶系,P1空间群,配合物2属于单斜晶系,P21/n空间群。  相似文献   

9.
合成并通过单晶衍射、元素分析及红外光谱表征了配合物[Ni(L12]·2DMF(1),[Cu(L12]·THF·0.25MeOH·2.25H2O(2),[Ni(L22]·2MeOH(3)和[Cu(L22]·2EtOH(4)的结构(HL1:5-甲酰基-3,4-二甲基-吡咯-2-甲酸乙酯缩硫代氨基脲,HL2:5-甲酰基-2,4-二甲基-吡咯-3-甲酸乙酯缩4-异丙基氨基硫脲)。单晶衍射结果表明,除溶剂分子不同外,配合物1~4的结构相似。每个配合物的中心金属离子分别与来自2个阴离子L-配体的N2S2电子供体配位,采取扭曲的平面正方形配位构型。荧光光谱结果表明,配合物与DNA的相互作用强于其配体。  相似文献   

10.
合成并通过单晶衍射、元素分析、红外光谱表征了配合物[(Cu)(L)(Cl)]·0.5EtOH·1.5H2O (1)和{[Zn(L)(NO3)]·2CH3CN}n (2)的结构(HL为PMBP缩4-甲基水杨酰肼; PMBP=1-phenyl-3-methyl-4-benzoyl-5-pyrazolone)。单晶衍射结果表明,配合物1中,Cu(Ⅱ)离子与来自烯醇化脱质子配体L-的2个O原子和1个N原子,及1个氯离子配位,采取扭曲的平面正方形配位构型。而配合物2中,Zn(Ⅱ)离子采取扭曲的三角双锥配位构型,与来自L-的NO2电子供体,1个单齿配位的硝酸根和相邻配体吡唑啉酮N原子配位,形成沿b轴方向的一维链状结构。在310 nm紫外光激发下,配合物2在434和459 nm处有很强的荧光发射,而配体的荧光发射峰在521 nm,强度明显弱于配合物。此外,固态配体和配合物2的荧光寿命分别为7.352 8和7.755 6 μs。  相似文献   

11.
溶剂萃取;二(乙基己基)膦酸;二(2-乙基己基)膦酸对镉(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)的萃取平衡  相似文献   

12.
The synthesis of the following crystalline complexes is described: [Li(L)(thf)2] (), [Li(L)(tmeda)] (), [MCl2(L)] [M=Al (), Ga ()], [In(Cl)(L)(micro-Cl)2Li(OEt2)2] (), [In(Cl)(L){N(H)C6H3Pri(2)-2,6}] (), [In(L){N(H)C6H3Pri(2)-2,6}2] (), [{In(Cl)(L)(micro-OH)}2] (), [L(Cl)In-In(Cl)(L)] () (the thf-solvate, the solvate-free and the hexane-solvate), [{In(Cl)L}2(micro-S)] () and [InCl2(L)(tmeda)] () ([L]-=[{N(C6H3Pri(2)-2,6)C(H)}2CPh]-). From H(L) (), via Li(L) in Et2O, and thf, tmeda, AlCl3, GaCl3 or InCl3 there was obtained , , , or , respectively in excellent yield. Compound was the precursor for each of , and [{InCl3(tmeda)2{micro-(OSnMe2)2}}] () by treatment with one () or two () equivalents of K[N(H)(C6H3Pri(2)-2,6)], successively Li[N(SiMe3)(C6H3Pri(2)-2,6)] and moist air (), Na in thf (), tmeda (), or successively tmeda and Me3SnSnMe3 (). Crystals of (with an equivalent of In) and were obtained from InCl or thermolysis of [In(Cl)(L){N(SiMe3)(C6H3Pri(2)-2,6)}] () {prepared in situ from and Li[N(SiMe3)(C6H3Pri(2)-2,6)] in Et2O}, respectively. Compound was obtained from a thf solution of and sulfur. X-Ray data for crystalline , , , , , and are presented. The M(L) moiety in each (not the L-free ) has the monoanionic L ligated to the metal in the N,N'-chelating mode. The MN1C1C2C3N2 six-membered M(L) ring is pi-delocalised and has the half-chair (, and ) or boat (, and ) conformation.  相似文献   

13.
A series of new rigid distibines, 1,8-bis(R(2)Sb)naphthalene (R = Me: (); R = Ph: ()), and chiral distibines, 2,2'-bis(R(2)Sb)-1,1'-binaphthyl (R = Me: (); R = Ph: () obtained as racemic mixtures) and the discrete enantiomers of 4,5-bis((R(2)Sb)methyl)-2,2-dimethyl-1,3-D/L-dioxolane (R = Me: () (l), () (d); R = Ph: () (l), () (d)) have been obtained in high yields, using either electrophilic halostibine reagents with di-lithium reagents (()-()) or nucleophilic stibide reagents with dibromo-derivatives (()-()). The distorted octahedral complexes [Mo(CO)(4)(L)], L = ()-(), planar [PtCl(2)(L)], L = (), (), (), (), and neutral, five-coordinate [RhCl(cod)(L)], L = (), (), (), are reported and trends in the spectroscopic data are discussed in terms of the ligand donor properties. Crystal structures of () and [Mo(CO)(4)()] reveal significant structural changes occur upon coordination, and these are also reflected in the solution NMR spectroscopic parameters. Changes in the C-Sb-C angles and C-Sb bond distances upon coordination of () are discussed in term of increased s/p orbital mixing. Air oxidation of () forms a very unusual stibine oxide, the structure of which shows a distorted Sb(4)O(4) cubane core (bridging O atoms) with two orthogonal naphthalene units.  相似文献   

14.
Complexes of the type [Au2(micro-PP3)2]X2 [X=Cl (), Br (), I ()], [Ag2(micro-PP3)2](NO3)2 (), Ag(PP3)Cl (), M3(micro-PP3)X3 [M=Au, X=Cl (), Br (), I (); M=Ag, X=NO3 ()] and Au4(micro-PP3)X4 [X=Cl (), Br (), I ()] have been prepared by interaction between gold(I) or silver(I) salts and the ligand tris[2-(diphenylphosphino)ethyl]phosphine (PP3) in the appropriate molar ratio. Microanalysis, mass spectrometry, IR and NMR spectroscopies and conductivity measurements were used for characterization. and are ionic dinuclear species containing four-coordinate gold(i) and four/three coordinate silver(i), respectively. Solutions of behave as mixtures of complexes in a 2:1 [Au2(micro-PP3)X2; X=Cl(), Br(), I()] and 4:1 () metal to ligand ratio. and react with free PP(3) in solution to generate the ionic compounds and , respectively. Complexes and , with four linear PAuX fragments per molecule, were shown by X-ray diffraction to consist of dimeric aggregates via close intermolecular gold(I)gold(I) contacts of 3.270 A () and 3.184 A (). The resultant octanuclear systems have an inversion center with two symmetry-related gold(I) atoms being totally out of the aurophilic area and represent a new form of aggregation compared to that found in other halo complexes of gold(I) containing polyphosphines. The luminescence properties of the ligand and complexes, in the solid state, have been studied. Most of the gold systems display intense luminescent emission at room and low temperature. The influence of the halogen on the aurophilic contacts of compounds with a 4:1 metal to ligand ratio results in different photophysical properties, while and are luminescent complex is nonemissive. The luminescence increases with increasing the phosphine/metal ratio affording for complexes , without aurophilic contacts, the stronger emissions. Silver complexes and are nonemissive at room temperature and show weaker emissions than gold(I) species at 77 K.  相似文献   

15.
The complexes [Ni{(SeP(i)Pr(2))(2)N}(2)] (), [Ni(Se(2)P(i)Pr(2))(2)] (), and [Co(Se(2)P(i)Pr(2))(2)] () were synthesised and the X-ray single crystal structures of () and () were determined. Thin films of nickel selenide, cobalt selenide and cobalt phosphide have been deposited by the chemical vapour deposition method using imidodiselenophosphinato-nickel(ii) (), -cobalt(ii) [Co{(SeP(i)Pr(2))(2)N}(2)] (), diselenophosphinato-nickel(ii) (), -cobalt(ii) () and diselenocarbamato-nickel(ii) [Ni(Se(2)CNEt(2))(2)] (), and -cobalt(iii) [Co(Se(2)CNEt(2))(3)] () precursors.  相似文献   

16.
The water-soluble Rh(I)-THP complexes: RhCl(1,5-cod)(THP) (), [Rh(1,5-cod)(THP)(2)]Cl (), RhCl(THP)(4) (), and trans-RhCl(CO)(THP)(2) () have been synthesized and characterized, where THP = P(CH(2)OH)(3); - are the first potentially useful entries into Rh(I)-THP chemistry, while and are the first structurally characterized Rh(I)-THP complexes.  相似文献   

17.
The preparation of 2-iminoimidazolines - has been accomplished by the Staudinger reaction of the carbenes 1,3-di-tert-butylimidazolin-2-ylidene (), 1,3-diisopropyl-4,5-dimethylimidazolin-2-ylidene (), 1,3-diisopropylimidazolin-2-ylidene (), 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene (), 1,3-bis(2,6-diisopropylphenylimidazolin-2-ylidene () and 1,3,4,5-tetramethylimidazolin-2-ylidene () with trimethylsilyl azide (Me3SiN3) followed by desilylation of the resulting 2-trimethylsilyliminoimidazolines -. The X-ray crystal structures of and have been established, revealing C1-N1-Si1 angles that are more obtuse than the corresponding P-N-Si angles observed in related trimethylsilyl iminophosphoranes. Together with , the disilylated side product 1,3-diisopropyl-2-(trimethylsilylimino)-4-trimethylsilylimidazoline () has been isolated and structurally characterized. Cleavage of the N-Si bonds in and formation of is easily achieved by stirring in methanol. The molecular structures of the 2-iminoimidazolines are reported, indicating that the structural parameters are best described by non-ylidic resonance structures and that electron delocalization within the imidazole heterocycle does not play a crucial role in these imine systems. Compound forms a head-to-head dimer in the solid state via weak intermolecular N-H...N contacts, which have additionally been characterized by means of compliance constants. To further analyze the electronic structure of these imines in comparison to related guanidine ligands, the proton affinities (PAs) of the model compounds 2-imino-1,3-dimethylimidazoline (), 2-imino-1,3-dimethylimidazolidine () and tetramethylguanidine () have been calculated by means of density functional theory. Finally, the charge distribution in - and the relative contribution of relevant resonance structures have been determined using natural bond orbitals (NBO) and natural resonance theory (NRT).  相似文献   

18.
镁(Ⅱ)对环丙沙星、小牛胸腺DNA间结合的调节作用   总被引:4,自引:0,他引:4  
近来的研究表明,喹诺酮类抗菌药物与细菌DNA分子间的结合可能受到介质离子强度等因素的影响[1,2].人们对镁(Ⅱ)在药物与DNA结合中所起的作用虽有研究[1,3],但多是从药理学的角度进行的[1~4].环丙沙星(CPFX)是目前临床上广泛使用的新一代...  相似文献   

19.
Stability constants of binary Fe(III)-methylcysteine, Cr(III)-methylcysteine and mixed Fe(III)-methylcysteine-cysteine, Cr(III)-methylcysteine-cysteine complexes have been determined by paper electrophoresis at 0.1 M ionic strength and a temperature of 35 degrees C. The stability constants of Fe(III)-methylcysteine-cysteine and Cr(III)-methylcysteine-cysteine mixed complexes were found to be 6.00 +/- 0.07 and 5.05 +/- 0.15 (logarithm of stability constant values), respectively.  相似文献   

20.
CoHR--H2O2-鲁米诺化学发光体系与应用   总被引:1,自引:0,他引:1  
研究了钛铁试剂(H2R2-)与Co(Ⅱ)形成的配合物CoHR-,对H2O2氧化鲁米诺的增强作用,基于此建立了钴的化学发光分析新方法。新方法Co(Ⅱ)的检出限为1.29×109g/L,工作曲线线性范围为5×108~1.0×105g/L,检测1×107g/LCo(Ⅱ)离子的相对标准偏差为2.5%以内。直接用于制药厂废水中微量钴的测定,结果满意  相似文献   

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