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1.
合成了新的O-(硫杂蒽酮-[2]-基)-氧乙酸及其稀土配合物.通过元素分析,IR,1HNMR,UV,DTA-TG和13CNMR谱对其结构进行了表征.研究表明:配体羧羰基脱质子后与金属离子配位,2位氧原子也与金属离子配位,配合物中含有一定量的配位水,配合物为非电解质类型.同时,研究了O-(硫杂蒽酮-[2]-基)-氧乙酸稀土配合物对质粒DNA的切割作用.结果表明:铕的配合物对DNA的切割较明显,且当配合物浓度增加时,质粒DNA的超螺旋构型逐渐减少,而缺刻、开环型构型逐渐增多.在相同条件下,Eu(III)离子对质粒pBR322DNA几乎没有切割作用;配体O-(硫杂蒽酮-[2]-基)-氧乙酸对质粒pBR322DNA也有切割作用,但配合物EuL3对质粒pBR322DNA的切割作用明显强于配体,表明稀土离子Eu(III)与配体生成配合物后有较好的协同切割作用.  相似文献   

2.
合成了新的O-(硫杂蒽酮-[2]-基)-氧乙酸及其稀土配合物.通过元素分析,IR,1H NMR,UV,DTA-TG和13C NMR谱对其结构进行了表征.研究表明:配体羧羰基脱质子后与金属离子配位,2位氧原子也与金属离子配位,配合物中含有一定量的配位水,配合物为非电解质类型.同时,研究了O-(硫杂蒽酮-[2]-基)-氧乙酸稀土配合物对质粒DNA的切割作用.结果表明:铕的配合物对DNA的切割较明显,且当配合物浓度增加时,质粒DNA的超螺旋构型逐渐减少,而缺刻、开环型构型逐渐增多.在相同条件下,Eu(Ⅲ)离子对质粒pBR322DNA几乎没有切割作用;配体O-(硫杂蒽酮-[2]-基)-氧乙酸对质粒pBR322DNA也有切割作用,但配合物EuL3对质粒pBR322DNA的切割作用明显强于配体,表明稀土离子Eu(Ⅲ)与配体生成配合物后有较好的协同切割作用.  相似文献   

3.
本文合成了两个具有平面萘环的二乙烯三胺配体:4-(α-萘甲基)-二乙烯三胺(L1)和4-( β-萘甲基)-二乙烯三胺(L2),用元素分析、NMR和ESI-MS等技术分别对它们进行了表征。通过电位滴定研究了这些配体的酸离解常数,它们与Cu(Ⅱ)离子结合的配位水分子的酸离解常数pKa值,与未修饰的二乙烯三胺的铜配合物相比,配合物的配位水分子的酸离解常数pKa值分别降低了1.09和0.59。这有利于配合物在接近生理pH值条件下对磷酸二酯键进行亲核活化。通过观察配体及其铜配合物对小牛胸腺DNA的粘度影响,证明配体和配合物可能以插入和部分插入两种方式与DNA作用。在无任何还原物质存在的条件下研究了两配体的铜配合物对质粒pBR322 DNA的断裂,结果表明两个配合物都能够有效切割超螺旋DNA为缺刻型DNA,且L1的铜配合物具有更高的核酸酶活性。  相似文献   

4.
为探讨过氧钒配合物上有机配体对反应平衡的影响, 在模拟生理条件下(0.15 mol/L NaCl溶液), 应用多核(1H, 13C和51V)多维(COSY) NMR以及变温技术等谱学方法研究双过氧钒配合物[OV(O2)2LL']n− [n=1~3, LL'=oxalate (缩写为oxa)、picolinate(缩写为pic)、bipyridine(缩写为bipy)和1,10-phenanthroline(缩写为phen), 与它们配位的含钒物种分别缩写为bpV(oxa), bpV(pic), bpV(bipy)和bpV(phen)]与N-甲基咪唑(缩写为N-Me-Im)的相互作用, 实验结果表明N-Me-Im与4种双过氧钒配合物的反应活性从强到弱的顺序为: bpV(oxa)>bpV(pic)>bpV(bipy)>bpV(phen). 研究表明金属中心上配体的配位能力和空间位阻都对反应平衡产生较大的影响, 同时竞争配位的结果导致新的过氧物种[OV(O2)2(N-Me-Im)]的生成, 而利用上述谱学方法则有助于揭示此类相互作用体系的反应过程和配位方式.  相似文献   

5.
为了探讨有机配体上取代基团对反应平衡的影响, 在模拟生理条件下(0.15 mol/L NaCl溶液), 应用多核(1H, 13C和51V)多维(COSY和DOSY) NMR以及变温技术等谱学方法研究双过氧钒配合物[OV(O2)2(D2O)]/[OV(O2)2(HOD)]N-取代皮考啉酰胺的相互作用. 它们反应性从强到弱的顺序为: N-甲基-皮考啉酰胺≈N-(2-羟乙基)-皮考啉酰胺>N-乙基-皮考啉酰胺>N-丙基-皮考啉酰胺, 这说明了皮考啉酰胺N上取代基的电子效应影响反应. 竞争配位导致一系列新的7配位的过氧钒物种生成, 而利用上述谱学方法则有助于揭示此类相互作用体系的反应过程和配位机制.  相似文献   

6.
利用易得的光学纯N-甲基氨基醇与1,2-双(二氯磷)乙烷缩合合成了一类新的具有C2对称轴的氮磷-氧磷配体(R,R)-双噁唑啉磷乙烷(BOAPE) 14. 该类配体不仅具有C2对称结构和刚性五元环, 还具有富电子特性, 利用500 MHz进行了1H NMR, 31P NMR, 13C NMR表征. 与这些配体配位形成的Rh配合物用于N-苯甲酰基脱氢丙氨酸衍生物和α-功能化酮不对称加氢, 分别可以得到99%和98%的ee. 这类配体比它们相对应的非C2对称的氮磷-氧磷化合物(AMPP)配体具有更高的对映选择性. 在这四个新的配体中配体(R,R)-Ph-BOAPE (2)的催化性能最优. 催化剂[Rh(COD)(R,R)-Ph-BOAPE]BF4的半反应周期t1/2和周转频率(TOF)在N-苯甲酰基肉桂酸甲酯的不对称加氢反应中分别为12 min和6.5 min-1.  相似文献   

7.
利用菲咯啉酮衍生物4-氯-2-(1H-咪唑并[4,5-f][1,10]菲咯啉)苯酚(HL)设计合成了一种新的单核铜配合物[Cu (L)(5-Cl-sal)(DMF)]ClO4·DMF (5-Cl-Hsal=5-氯-水杨醛),用元素分析和X射线单晶衍射等手段对配合物进行了表征。该配合物晶体属三斜晶系,P1空间群。用紫外吸收光谱、荧光光谱和凝胶电泳等方法研究了配合物与DNA的相互作用。结果表明,配合物以插入方式与CT-DNA结合,结合常数为1.02×103 L·mol-1。同时配合物也能较大程度淬灭EB-DNA复合物的荧光,表观键合常数为4.37×105 L·mol-1,略小于经典键合常数107 L·mol-1。淬灭机理为动态淬灭。凝胶电泳实验研究表明配合物在H2O2存在下可将pBR322质粒DNA切割为开环缺口型DNA和线型DNA,配合物浓度越大,切割效果越好。机理研究显示,配合物切割DNA的反应是由羟基自由基(·OH)和单线态氧(1O2)作为活性物种的氧化切割过程。  相似文献   

8.
以2-苯氧乙醇为起始剂, 合成了两种新型氮支套索冠醚: N-(2-苯氧乙基)单氮杂-18-冠-6 (18CE)与N-(2-苯氧乙基)单氮杂-15-冠-5 (15CE). 通过红外光谱、核磁共振氢谱和紫外光谱表征了新冠醚及其中间体的结构. 用电导滴定法研究了两冠醚与Na, K, Ag, NH4+, Ni2+, Cu2+, Pb2+和Co2+在25 ℃的配位作用, 计算了1∶1配合物的稳定常数. 实验结果表明, 由于N-(2-苯氧乙基)引入氮杂冠醚环和参与配位, 18CE和15CE配合物的稳定常数分别比单氮杂-18-冠-6, N-(2-羟基乙基)单氮杂-18-冠-6, N-(2-甲氧基乙基)单氮杂-18-冠-6和单氮杂-15-冠-5, N-(2-甲氧乙基)单氮杂-15-冠-5, N-(2-甲氧乙基)单氮杂-15-冠-5的对应配合物明显提高. 配合物的稳定常数和紫外光谱皆提供了支链的苯氧基参与配位的信息.  相似文献   

9.
制备了2个新的含有N,N,N-三甲基丙烷-1-铵基团和N,N,N-三甲基戊烷-1-铵基团的苯乙酮-(4-羟基苯腙)配体:(E)-3-(4-(1-(2-(4-hydroxybenzoyl)hydrazono)ethyl)phenoxy)-N,N,N-trimethylpropan-1-ammonium perchlorate(H2L1)和(E)-3-(4-(1-(2-(4-hy-droxybenzoyl)hydrazono)ethyl)phenoxy)-N,N,N-trimethylpentane-1-ammonium perchlorate(H2L2)。以这2个配体分别合成了2个新的铜配合物:[Cu(HL12]和[Cu(HL22],研究了这些配体和配合物的DNA结合和切割活性,还研究了DNA切割的机理以及化合物浓度对DNA切割反应的影响。紫外-可见光谱结果表明,所有化合物均优先通过主沟结合模式与DNA结合,在甲基绿(主要的沟结合剂)的存在下切割DNA的活性受到抑制的结果也支持这一结论。电泳研究的结果则表明,化合物在存在或不存在氧化剂(H2O2)的情况下均对质粒DNA表现出显著的切割活性,活性主要取决于化合物的浓度。化合物通过水解途径裂解pBR322DNA,在存在不同自由基清除剂情况下的DNA裂解实验也支持这一结论。  相似文献   

10.
高恩君  李浩洋  刘祁涛 《化学学报》2005,63(13):1225-1230
合成了配合物[Pd(L-tyr)2]•0.5H2O单晶(L-tyr为酪氨酸根). 配合物属于单斜晶系, P2(1)空间群. L-tyr的羧基氧原子和氨基氮原子与Pd(II)离子配位, 形成两个五元螯合环的平面结构. 配合物分子之间存在配位螯合环-配位螯合环的弱相互作用、苯酚环-苯酚环之间的π-π堆积作用以及水分子与配体之间的氢键作用. 水溶液中配合物的累积稳定常数为1017数量级, 表明配体与离子形成较强的配位共价键. 配合物与鱼精DNA作用的紫外光谱、CD光谱和荧光光谱表明, 两者之间有较强的相互作用, 并以插入作用方式为主.  相似文献   

11.
利用2,3-二苯基喹喔啉和水合三氯化铱(IrCl3?H2O)反应, 合成了一种新型喹喔啉铱的配合物[Ir(DPQ)2(acac)], 通过元素分析, 1H NMR和HRMS对配合物结构进行了表征, 结果显示得到的是目标化合物. 利用紫外光谱和荧光光谱对配合物的吸收光谱和光致发光光谱进行了研究. 利用该材料作为磷光材料制备了结构为[ITO/NPB(30 nm)/NPB∶7% Ir(DPQ)2(acac)(25 nm)/PBD (10 nm)/Alq3 (30 nm)/Mg∶Ag (10∶1)(120 nm)/Ag(10 nm)] 的电致发光器件, 研究了其电致发光光谱. 结果表明, 配合物[Ir(DPQ)2(acac)]在476和625 nm处存在单重态1MLCT(金属到配体的电荷跃迁)和三重态3MLCT的吸收峰; 发光光谱结果显示, 在660 nm处有较强的金属配合物三重态的磷光发射; 电致发光光谱显示, 该器件的启动电压是4.25 V, 器件的最大亮度为4910 cd/m2, 外量子效率为5.14%, 器件的流明效率为1.12 lm/W, 是一种新型红色磷光材料.  相似文献   

12.
一种双核铕配合物的合成、光致发光和电致发光性质研究   总被引:5,自引:0,他引:5  
合成了一个新的双核铕配合物Eu(TTA)3(tpphz)Eu(TTA)3(其中TTA=去质子化的α-噻吩甲酰三氟丙酮; tpphz=[3,2-a:2',3'-c:3',2'-h:2'',3''-j]四吡啶基吩嗪). 研究了该配合物的光致发光和电致发光性质. 一个四层电致发光器件ITO/TPD, 10 nm/Eu(TTA)3(tpphz)Eu(TTA)3, 20 nm/BCP, 20 nm/AlQ, 40 nm/Mg0.9Ag0.1, 200 nm/Ag, 100 nm表现出中心在633 nm处的宽带红光发射, 该宽带发射可能来源于双核Eu(III)配合物和TPD形成的激基复合物. 该器件的启动电压为10 V, 在18 V和135 mA/cm2时的最大亮度达146 cd/m2.  相似文献   

13.
合成了两种新型三齿多吡啶钴(II)和钌(II)的混配配合物[Co(TolylTPy)(H2Bzimpy)]Cl2 [TolylTPy=4'-对甲基苯 基-2,2':6',2'-三联吡啶, H2Bzimpy=2,6-二(苯并咪唑-2)吡啶] (A)和Ru(TolylTPy)(Bzimpy) (B). 用元素分析, IR, 1H NMR等对它们进行了表征, 测定了配合物B的晶体结构, 用电子吸收光谱、荧光光谱等研究了配合物与小牛胸腺DNA(CTDNA)的相互作用及其对pBR322 DNA的断裂作用. 结果表明, 配合物A和B与CTDNA的作用属静电结合, 凝胶电泳实验说明配合物A在310 nm光辐射15 min, 可使超螺旋pBR322 DNA断裂为开环缺口型和线型DNA.  相似文献   

14.
A novel method for the N?N bond cleavage of trimethylsilyl diazomethane is reported for the synthesis of terminal nitride complexes. The lithium salt of trimethylsilyl diazomethane was used to generate a rare terminal nitrilimine transition metal complex with partially occupied d‐orbitals. This iron complex 2 was characterized by CHN combustion analysis, 1H and 13C NMR spectroscopic analysis, single‐crystal X‐ray crystallography, SQUID magnetometry, 57Fe Mössbauer spectroscopy, and computational analysis. The combined results suggest a high‐spin d 6 (S=2) electronic configuration and an allenic structure of the nitrilimine ligand. Reduction of 2 results in release of the nitrilimine ligand and formation of the iron(I) complex 3 , which was characterized by CHN combustion analysis, 1H NMR spectroscopic analysis, and single‐crystal X‐ray crystallography. Treatment of 2 with fluoride salts quantitatively yields the diamagnetic FeIV nitride complex 4 , with concomitant formation of cyanide and trimethylsilyl fluoride through N?N bond cleavage.  相似文献   

15.
An asymmetric ligand (pdpiq?=?2-(pyridine-2-yl)-6,7-diphenyl-1-H-imidazo[4,5-g]quinoxaline) and its ruthenium complexes with [Ru(L)2pdpiq]2+ (L?=?bpy (2,2′-bipyridine) or phen (1,10-phenanthroline)) have been synthesized and characterized by elemental analysis, ES-MS, and 1H NMR. The DNA-binding behaviors of these complexes were studied by spectroscopic methods and viscosity measurements. The results indicate that the complexes can intercalate into DNA base pairs. When irradiated at 365?nm, the two complexes promote the cleavage of plasmid pBR322DNA. The mechanism of DNA cleavage is an oxidative process by generating singlet oxygen.  相似文献   

16.
《Polyhedron》2002,21(18):1837-1844
This work reports the synthesis, characterization and spectroscopic studies of Eu(III)-perchlorate complexes with amide ligands derived from N-[x-methylpyridyl]acetamide where x=3, 4 and 6. The Eu(ClO4)33(x-mpa) complexes were characterized by elemental analyses, molar conductance, TG analyses and vibrational spectroscopy. Raman and infrared data show that the perchlorate ion, (ClO4 ), is bonded to Eu(III) as a monodentate ligand and that in these three complexes water molecules are not coordinated to the rare earth ion. The profiles of the emission spectra of the complexes with 3- and 4-mpa ligands are very similar but they differ from the complex containing 6-mpa ligand. This spectroscopic behavior can be rationalized in terms of the Ωλ (λ=2 and 4) and R02 experimental intensity parameters. The values of Ω2 (∼6.5×10−20 cm2) in these complexes are smaller than in Eu(III)-TTA compounds (Ω2∼35.0×10−20 cm2), indicating that in the former case the rare earth ion is in a chemical environment less polarizable. Lifetime and emission quantum efficiency measurements for the emitting level 5D0 were carried out and the results are discussed.  相似文献   

17.
合成了O-(硫杂蒽酮-[2]-基)-氧乙酸镍(II)配合物。通过元素分析,IR, DTA-TG谱对其结构进行了表征。研究表明:配体羧羰基脱质子后与镍离子配位,配合物中含有一定量的配位水。同时以紫外可见光谱、荧光光谱、园二色谱,电化学方法和凝胶电泳方法研究了该配合物与DNA的作用。结果表明,该配合物能在生理条件下比配体和金属离子更有效地切割质粒DNA,自由基捕捉剂的加入不影响配合物的切割活性。该配合物使DNA溶液的紫外吸收强度和园二色吸收强度降低,DNA的存在可使该配合物的氧化还原活性降低。与溴化乙锭和DNA的竞争反应说明,该配合物主要以嵌入方式与DNA结合。  相似文献   

18.
(Z)-4-(4-Methoxyphenoxy)-4-oxobut-2-enoic acid and its solid rare earth complexes LnL3.2H2O (Ln=La, Eu, Tb) were synthesized and characterized by means of MS, elemental analysis, FTIR, 13C NMR and TG-DTA. The IR and 13C NMR results show that the carboxylic groups in the complexes coordinated to the rare earth ions in the form of a bidentate ligand, but the ester carboxylic groups have not taken part in the coordination. The luminescence spectra of Eu(III) and Tb(III) complexes in solid state were also studied. The strong luminescence emitting peaks at 616nm for Eu(III) and 547nm for Tb(III) can be observed, which could be attributed to the ligand has an enhanced effect to the luminescence intensity of the Eu and Tb.  相似文献   

19.
Two novel pyrazole-derived ligands, 3-chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinic acid (CDPA) and 3-chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)-N-phenylpicolinamide (CDPP) were prepared by 3,6-dichloropicolinic acid (DCPA). Their complexes with terbium(III) and europium(III) were synthesized. The complexes were characterized by elemental analysis, infrared spectra, 1H NMR and TG–DTG. Furthermore, the above complexes using 1,10-phenanthroline as a secondary ligand were also synthesized and characterized. The luminescence properties of these complexes in solid state were investigated. The results suggested that Tb(III) complexes exhibit more efficient luminescence than Eu(III) complexes and the fluorescence of the complexes with 1,10-phenanthroline as a secondary ligand was prominently stronger than that of complexes without this ligand., and the three ligand (DCPA), (CDPP) and (CDPA) are excellent sensitizers to Eu(III) and Tb(III) ion.  相似文献   

20.
Diorganotin(IV) complexes ( 1‐4) of MESNA (sodium 2‐mercaptoethanesulfonate HSCH2CH2SO3Na) and a mixed ligand complex of dibutyltin(IV), 1,10‐phenanthroline and MESNA ( 5 ) were synthesized with thermal and microwave assisted methods. All the complexes were characterized thoroughly with the help of analytical and various spectroscopic techniques viz. FTIR, NMR (1H, 13C, and 119Sn NMR) spectroscopy and ESI‐MS spectrometery. Various spectrophotometric studies were carried out to decipher the binding mode of MESNA and its diorganotin complexes 1 ‐ 5 with calf thymus DNA (CT DNA) and thus, to calculate the binding constant (Kb). Absorption spectrophotometric study confirmed the interaction is through partial intercalation of all the complexes including MESNA, inside the DNA helix and calculated binding constant (Kb) is in the order of 103 M‐1. A series of emission spectrophotometric experiments support the results obtained through the absorption spectrophotometric studies. Circular dichroic (CD) spectroscopic analysis and viscosity measurement of CT DNA further complemented the fact that the partial intercalation plays a major role in the interaction of the studied complexes with CT DNA. All the studies corroborated that complex 2 bound to CT DNA with maximum affinity followed by complex 5 among all the complexes. Involvement of hydroxyl radicals as an active species in the cleavage activity of pBR322 plasmid DNA is proved by carrying out agarose gel electrophoretic technique.  相似文献   

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