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1.
本文合成6种带有席夫碱基团的螺吡喃光致变色化合物,并利用电子吸收光谱、荧光光谱研究了它们的光谱性质以及与DNA的相互作用,考察了不同基团对其作用的影响,对同一化合物研究了在不同pH值、不同离子强度条件下的作用情况,初步探讨了它们与DNA的作用方式.  相似文献   

2.
采用电化学和光谱法,研究了糠醛缩对氨基苯磺酸席夫碱Cu(Ⅱ)配合物与鲱鱼精DNA的相互作用。结果发现:糠醛缩对氨基苯磺酸席夫碱Cu(Ⅱ)中加入DNA后,氧化还原峰电流降低,式量电位正移;席夫碱Cu(Ⅱ)配合物使DNA的最大吸收峰强度增强,DNA使席夫碱Cu(Ⅱ)配合物的荧光强度增强。表明席夫碱Cu(Ⅱ)配合物以嵌插模式与DNA作用。  相似文献   

3.
通过异烟肼和4-N,N-二羟乙基苯甲醛来合成一种席夫碱及其锡配合物,并通过核磁、元素分析以及X-射线单晶衍射来进行结构表征。该平面构型的席夫碱采取二齿配位模式,其中的-C=N-在配位后由反式变为顺式。晶体结构数据以及荧光光谱中的显著红移现象表明锡配合物中的π-共轭体系通过配位反应得以延展。体外细胞毒性数据表明,席夫碱配体及其锡配合物对于A-549,MCF-7和Hela等肿瘤细胞的生长抑制活性要强于顺铂。还通过紫外可见光谱及荧光光谱初步研究了两种化合物与DNA的相互作用,结果表明锡配合物可能通过共价结合来导致DNA双螺旋链变形,而席夫碱分子中的氢键效应及其长平面结构可能会阻碍其嵌入DNA双螺旋链。  相似文献   

4.
水溶性不对称卟啉及其金属配合物合成及与DNA的 作用   总被引:5,自引:1,他引:4  
韩高义  杨频 《化学学报》2001,59(6):925-930
合成并表征了三(4-N-甲基吡啶基)卟啉为母体,带有乙氧羰基甲氧基或羧基甲氧基侧链的水溶正电性卟啉及其金属配合物(M=Cu,Ni),并研究了它们与DNA的相互作用。卟啉对EB-DNA荧光猝灭研究表明:卟啉与DNA作用存在单一结合模式。EB荧光竞争法测得它们与DNA作用的结合常数介于3×10^5~3×10^6L·mol^-1。电子吸收研究谱表明:DNA引起卟啉Soret带的不同程度的红移(≤9nm)和减色(≤35%)。卟啉及其金属配合物都引起DNA的熔点升高(≤2.5℃)和DNA粘度的略微下降。所有这些研究表明:这些带较长侧链的水溶性卟啉及其金属配合物与DNA作用不存在插入作用模式,只是在DNA的外部结合。  相似文献   

5.
通过异烟肼和4-N,N-二羟乙基苯甲醛来合成一种席夫碱及其锡配合物,并通过核磁、元素分析以及X-射线单晶衍射来进行结构表征。该平面构型的席夫碱采取二齿配位模式,其中的-C=N-在配位后由反式变为顺式。晶体结构数据以及荧光光谱中的显著红移现象表明锡配合物中的π-共轭体系通过配位反应得以延展。体外细胞毒性数据表明,席夫碱配体及其锡配合物对于A-549,MCF-7和Hela等肿瘤细胞的生长抑制活性要强于顺铂。还通过紫外可见光谱及荧光光谱初步研究了两种化合物与DNA的相互作用,结果表明锡配合物可能通过共价结合来导致DNA双螺旋链变形,而席夫碱分子中的氢键效应及其长平面结构可能会阻碍其嵌入DNA双螺旋链。  相似文献   

6.
合成了水溶性四-[(4-三甲铵基)苯基]卟啉TAPP及其金属卟啉化合物MTAPP,其中M=Zn(Ⅱ),,Cu(Ⅱ),Fe(Ⅲ),Co(Ⅲ),Ni(Ⅱ),Mn(Ⅲ),通过元素分析,紫外-可见光谱确定了化合物的组成和结构,以紫外-可见光谱,荧光光谱及粘度法等手段了卟啉化合物TAPP和金属卟啉化合物ZnTAPP与小牛胸腺DNA的相互作用,结果表明,TAPP,ZnTAPP与DNA相互作用使紫外-可见光谱发生了8-12nm的红移,并出现了明显的减效应,荧光光谱强度明显增大,吸收峰位发生变化,以艾氏腹水癌(Ac)和肝癌(Hept)细胞为靶细胞,采用MTT染色法评价了化合物的抗癌活性,部分化合物表现出较高的抗癌活性。  相似文献   

7.
合成了三种铕(III)与牛磺酸缩水杨醛席夫碱配合物 [(Eu(TSal)L(NO3)) •2H2O,TSal :席夫碱配体,L1:1,10-邻菲咯啉,L2:2- 氨基吡啶,L3:2,2’-联吡啶],并对其进行了结构表征;采用荧光光谱法和粘度法研究了配合物与小牛胸腺DNA的相互作用模式。实验结果表明三种配合物对DNA均有不同强度的插入作用,其插入能力在一定范围内与配合物的浓度正相关,且与配合物分子适宜的平面性有关,三种配合物对DNA插入能力顺序为:[Eu(TSal)L1(NO3)]•2H2O>[Eu (TSal)L3(NO3)] •2H2O>[Eu(TSal) L2(NO3)]• 2H2O。  相似文献   

8.
双嘧达莫的荧光光谱分析法   总被引:9,自引:0,他引:9  
以荧光光谱法研究了双嘧达莫在溴化十六烷基三甲基铵(CTMAB)、β_环糊精 (β_CD)、十二烷基硫酸钠 (SDS)等介质体系中的荧光性质 ,发现CTMAB、SDS和 β_CD对双嘧达莫均有不同程度的荧光增敏作用 ,提出了在CTMAB、SDS和 β_CD水溶液中测定双嘧达莫的荧光光谱分析法 ;该法灵敏度高 ,检出限低(3.20×10 -9mol/L) ,在6.40×10 -8~3.20×10 -6mol/L范围内荧光强度与双嘧达莫的浓度呈良好线性关系  相似文献   

9.
研究了水溶性β-环糊精交联聚合物对含有双苯环的芳香席夫碱的荧光增强作用。发现除介质酸度外,双苯环客体间的距离是决定荧光增强程度的重要因素。当双苯环间隔3 ̄4个原子时,分子发射荧光的能力明显增强。β-环糊精交联聚合物的这种特殊的立体选择性表明,其有可能成为一种新的分子荧光识别手段,并为β-环糊精交联聚合物应用于荧光增敏体系提供了理论基础。  相似文献   

10.
左炔诺孕酮的荧光光谱分析法   总被引:10,自引:1,他引:9       下载免费PDF全文
用荧光光谱法研究了硫酸介质中左炔诺孕酮与 β_环糊精主客体包络反应的条件及机理 ,以及溴化十六烷基三甲铵的增敏作用 ,提出了在水溶液中测定左炔诺孕酮的荧光光谱分析法;该法灵敏度高 ,检出限低(3.20×10 -8mol/L) ,荧光强度与左炔诺孕酮浓度在6.40×10 -8~3.20×10 -6mol/L范围内呈良好线性关系 ,方法的相对标准偏差为0.9 %(n=5)。  相似文献   

11.
The fluorescence spectral characteristics and the interaction of several water-soluble metal complexes of Schiff-base with DNA are described. Among the complexes tested, Mn-Schiff-base bound to DNA showed a marked decrease in the fluorescence intensity with a blue shift of the excitation and emission peaks. Some hypochromism in the UV absorption spectra was also observed. KI quenching and competitive binding to DNA between Mn-Schiff-base and ethidium bromide (EB) were studied in connection with other experimental observations to show that the interactive model between Mn-Schiff-base and DNA is an intercalative one. The pH and salt effect on the fluorescence properties was also investigated. The linear relationship between F/F0 and the concentration of calf thymus DNA covers 3.0 x 10(-6)-2 x 10(-4) mol L-1, which can be utilized for determining traces of calf thymus DNA with a detection limit of 8.0 x 10(-7) mol L-1 in base pairs.  相似文献   

12.
合成了一种新颖三齿配体(L),N-(4-甲基苯)-N’-(2-(4-甲基苯氨基)乙基)乙烷-1,2-二胺,并制备了它的四种过渡金属配合物,结合元素分析、红外、1 HNMR和摩尔电导,确定配合物的组成为[ML(NO3)2](M=CuⅡ,CoⅡ,NiⅡ,ZnⅡ).用X-ray单晶衍射解析了Zn-L和Ni-L的单晶结构.通过紫外、荧光光谱研究了这四种金属配合物与小牛胸腺DNA的相互作用,根据结果推断出配合物与DNA的作用方式可能均为静电结合.Cu-L,Co-L,Ni-L,Zn-L与DNA的结合常数分别为:3.34×104,7.65×103,2.15×104,2.40× 104.  相似文献   

13.
The fluorescence spectral characteristics and interaction of bis(ethylene)tin(bis(salicylidene)ethylenediamine) [Et2Sn(salen)] with DNA are described. The polarity of the solvent has a strong effect on the fluorescence characteristics of Et2Sn(salen). Et2Sn(salen) bound to DNA showed a marked decrease in the fluorescence intensity with a bathochromic shift of the excitation and emission peaks. A hypochromism in the UV absorption spectra was also observed. KI quenching and competitive binding to DNA between Et2Sn(salen) and ethidium bromide (EB) were studied in connection with other experimental observations to show that the interactive model between Et2Sn(salen) and DNA is an intercalative one. The pH and salt effect on the fluorescence properties was also investigated. The intrinsic binding constant was estimated to be 1.071 x 10(5) mol L(-1) in base pairs and the binding site number is 1.98, respectively. A linear relationship between F/F0 and the concentration of calf thymus DNA covers 5.1 x 10(-6) - 2.41 x 10(-4) mol L(-1), which can be utilized for determining traces of calf thymus DNA with a detection limit of 1.1 x 10(-7) mol L(-1) in base pairs.  相似文献   

14.
A series of chalcone derivatives (1-4) were studied. The interaction between these ligands and calf thymus DNA was studied with UV-vis spectrophotometry, fluorescence and circular dichroism spectroscopy. The binding constants K were estimated at 0.5-4.6×10(5) M(-1). All these measurements indicated that the compounds behave as effective DNA-intercalating agents. Electrophoretic separation proved that ligands inhibited topoisomerase I at a concentration of 60 μM.  相似文献   

15.
Chiral Schiff base ligands (S)-H(2)L and (R)-H(2)L and their complexes (S-Ni-L, R-Ni-L, S-Cu-L, R-Cu-L, S-Zn-L and R-Zn-L) were synthesized, characterized and examined for their DNA binding, antioxidant and antibacterial activities. The complexes showed higher binding affinity to calf thymus DNA with binding constant ranging from 2.0×10(5) to 4.5×10(6) M(-1). All the complexes also exhibited remarkable superoxide (56-99%) and hydroxyl scavenging (45-89%) activities as well as antibacterial activities against gram (+) and gram (-) bacteria. However, none of the complexes showed antifungal activity. Conclusively, S enantiomers of the complexes were found to be relatively more efficient for DNA interaction, antioxidant and antibacterial activities than their R enantiomers. This study reveals the possible utilization of chiral Schiff base complexes for pharmaceutical applications.  相似文献   

16.
New sensitive, reliable and reproducible fluorimetric methods for determining microgram amounts of nucleic acids based on their reactions with Fe(II), Os(III) or Sm(III) complexes of 4,7-diphenyl-1,10-phenanthroline are proposed. Two complementary single stranded synthetic DNA sequences based on calf thymus as well as their hybridized double stranded were used. Nucleic acids were found to react instantaneously at room temperature in Tris-Cl buffer pH 7, with the investigated complexes resulting in decreasing their fluorescence emission. Two fluorescence peaks around 388 and 567 nm were obtained for the three complexes using excitation lambda(max) of 280 nm and were used for this investigation. Linear calibration graphs in the range 1-6 microg/ml were obtained. Detection limits of 0.35-0.98 microg/ml were obtained. Using the calibration graphs for the synthetic dsDNA, relative standard deviations of 2.0-5.0% were obtained for analyzing DNA in the extraction products from calf thymus and human blood. Corresponding Recovery% of 80-114 were obtained. Student's t-values at 95% confidence level showed insignificant difference between the real and measured values. Results obtained by these methods were compared with the ethidium bromide method using the F-test and satisfactory results were obtained. The association constants and number of binding sites of synthetic ssDNA and dsDNA with the three complexes were estimated using Rosenthanl graphic method. The interaction mechanism was discussed and an intercalation mechanism was suggested for the binding reaction between nucleic acids and the three complexes.  相似文献   

17.
两个多胺铜配合物的合成,晶体结构以及DNA切割活性   总被引:2,自引:2,他引:0  
本文以配体N,N′-二(3-氨丙基)-4-甲氧基苄胺(amba)与4,4′-联吡啶,铜盐反应合成了两种多胺Cu(Ⅱ)配合物[Cu(amba)Cl2](1)和[Cu(4,4′-bipy)(amba)(ClO4)]ClO4(2),通过红外光谱、质谱和X-射线单晶衍射对其结构进行了表征。利用紫外吸收光谱、分子荧光,电化学以及粘度试验研究了配合物与小牛胸腺DNA(CT-DNA)的相互作用方式。通过紫外吸收光谱得到配合物1和2与DNA的结合常数Kb分别为1.3×104 mol-1.L和1.7×104 mol-1.L,荧光光谱得到配合物1和2的荧光淬灭常数分别为1.04×103mol-1.L和1.81×103 mol-1.L,表明了配合物1和2与CT-DNA结合方式均为静电模式。凝胶电泳实验的结果表明配合物对pBR322 DNA的切割均为水解切割。  相似文献   

18.
We have used circular dichroism, hydrodynamic methods, absorbance, and fluorescence titration to study the interaction of 4-anilinopyrimido[4',5':4,5] selenolo (2,3-b)quinoline (APSQ) and 4-piperazinopyrimido[4',5':4,5] selenolo(2,3-b)quinoline (PPSQ) with DNA. The association constants of APSQ and PPSQ were of the order of 10(4)M(-1). The fluorescence properties at ionic strength 0.01M are best fit by the neighbor exclusion model, with K=0.58-9.2 x 10(4)M(-1) and an exclusion parameter of 0.9-6.4 bp. Binding to the GC-rich DNA of Micrococcus lysodeikticus was stronger than the binding to calf thymus DNA, suggest that drug binds preferentially to G+C pairs at low r. CD spectra indicate that stacking of these compounds with DNA induces a strong helicity in the usually disordered structure of this double strand. Viscosity experiments show with sonicated calf thymus DNA with PPSQ an twice increase in slope (m) as that with APSQ. PPSQ increases the T(m) for calf thymus DNA melting by approximately 10 degrees C as binding approaches saturation, with biphasic melting. The cytotoxicities of these compounds on leukemia HL-60, K-562, B16F10 melanoma and Colo-205 are quite similar and inhibition (IC(50)) was in the range of 0.39-9.80 microM. The anticancer efficacy against B16F10 melanoma has provided evidence of major anticancer activity for PPSQ. Single or multiple intraperitonial (i.p.) doses of drug proved high level activity against the subcutaneous (s.c.) grafted B16 melanoma, significantly increase in life span (ILS 139% and 170%). The aim of this study was to analyze the physiochemical properties of these compounds in an attempt to understand its superior biological activity.  相似文献   

19.
邻香草醛缩牛磺酸Schiff碱铕(Ⅲ)配合物与DNA的插入作用   总被引:1,自引:0,他引:1  
合成了3种铕(Ⅲ)与邻香草醛缩牛磺酸Schiff碱配合物[EuTOvL(NO3)]·2H2O(TOy:Schiff碱配体,L^1:1,10-邻菲咯啉,L^2:2,2'-联吡啶,L^3:2-氨基吡啶),并对其进行了结构表征;采用荧光光谱法和黏度法研究了配合物与DNA的相互作用模式.实验结果表明3种配合物对DNA均有不同强度的插入作用,其插入能力在一定范围内与配合物的浓度正相关,且与配合物分子适宜的平面性有关,3种配合物对DNA插入能力顺序为:[EuTOvL^1(NO3)]·2H2O〉[EuTOvL^2(NO3)]·2H2O〉[EuTOvL^3(NO3)]·2H2O.  相似文献   

20.
Summary A series of new complexes [RuL2(pdphen)]2+, where pdphen is the planar ligand pyridino[3,2-f] [1,7]phenanthroline and L = 2,2-bipyridine, phenanthroline, 2,9-dimethylphenanthroline or 5-nitrophenanthroline, were prepared and characterized. The binding of [RuL2-(pdphen)] 2+ to calf thymus DNA was investigated using absorption, fluorescence and circular dichroism (c.d.) spectroscopies. All of the complexes show absorption hypochromicity associated with binding to calf thymus DNA. [Ru(bipy)2pdphen]2+ and [Ru(phen)2pdphen]2+ also show fluorescence intensities and excited state life-time increases. The c.d. spectra of dialyzates from solutions of racemic complexes versus calf thymus DNA indicate enantioselectivity associated with binding to DNA.  相似文献   

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