6-苄氨基嘌呤及其金属配合物与DNA的作用机理

新型抗癌症药剂的开发和抗癌机理研究,一直是人们争相研究的前沿课题[1-5]。而许多预防和治疗癌症的药物都是以D N A为作用靶来设计的[6]。以D N A为靶分子的金属抗癌剂,其抗癌活性是由于金属离子与D N A的配位,即金属离子与D N A的某些亲核基团(如磷酸氧位点或碱基氮、氧位点)     

全细胞膜片钳法研究铜对急性分离大鼠海马细胞钾电流的影响

Using the whole cell patch clamp technique, the effect of Cu^2＋on transient outward K^＋current （/to） and delayed rectifier K^＋ current （Idr） was studied in acutely isolated rat hippocampal neurons.Ito and Idr were increased when the concentration of Cu^2＋ was lower than 2 × 10^-5 and 10^-5 tool/L, respectively, and increased ratio was decreased with increasing Cu^2＋concentration in the bath solutions. When the concentration continued to increase to 5× 10^-5 and 2 × 10^- 5 mol/L, the currents were hardly changed, while the concentration was more than 10^-4 and 5 × 10^-5 mol/L, the currents were inhibited remarkably. Cu^2＋ （10^-5 mol/L） did not affect the activation and inactivation process of Ito. The activation curve of Idr was shifted toward positive potential, but 10^-5 mol/L Cu^2＋did not affect slope factor. According to these results, it was considered that Cu^2＋at low concentration in the bath solution could promote Ito and Idr while at high concentration could inhibit them, and change of amplitude was different with different membrane voltage. Conclusion was drawn： Cu^2＋may be involved in the pathophysiologic mechanism of diseases with neuropathological components.     

生物大分子的构型能量分析

我们将前人发展的半经验构型能量分析方法用来计算聚糖、多肽、聚核苷酸分子的构型能量,并发展了一种计算各种生物聚分子构型能量的一般计算方法。已编写出FORTRAN语言的计算机程序。用这种方法巳完成如下计算。 1.聚糖类大分子是基本的生物聚分子之一。晶体结构研究表明,聚糖链中吡喃糖环的构型变化很小,链     

α-球蛋白与稀土金属离子钆(Ⅲ)的配位作用

采用固定顺磁金属离子浓度,逐渐改变α-球蛋白浓度,测定溶剂水质子弛豫时间变化的方法,研究了稀土离子钆(Ⅲ)与人血α-球蛋白的配位作用.研究结果表明,α-球蛋白中有3个钆(Ⅲ)离子的结合部位,其配合物的离解常数K_d=2.5×10~(-4)(mol/L)。     

Coordination field analysis of rare earth complexes with triangular symmetry

The calculation of the complex matrixes in odd triangular symmetry was accomplished.The configurations of the coordination unit with various triangular symmetries and different ligand numbers were discussed.On the basis of the double-sphere coordination point-charge (DSCPCF) model,the detailed forms of the DSCPCF parameters Bmk and the expressions of the perturbation matrix elements in triangular field (D3,D3h,D3d) were derived.Thereby,the calculation scheme of coordination field perturbation energy of the rare earth complexes with triangular symmetry was constructed After the calculation scheme was programmed,the Stark energies of the crystalline TbAl3(BO3)4 were calculated The results were considerably close to the experimental values     

多吡啶锌配合物键合与切割DNA研究

The complex of Zn[(phen)(dione)Cl]ClO_4·H_2O(where phen is 1,10-phenanthroline and dione is 1,10-phenan-throline-5,6-dione)has been synthesized and characterized.The interaction of the complex with DNA was investi-gated using UV absorption,fluorescence spectroscopy and electrophoresis measurements.The results show that thecomplex mainly binds to the double helix of DNA with intercalation mode and the binding constant K is 2.4×10~4mol~(-1)·L.Moreover,the complex can efficiently cleave plasmid DNA at physiological pH and temperature.Thecleavage occurs via a hydrolysis mechanism,which is showed by adding radical scavengers,rigorously anaerobicexperiments,analysis for malondialdehyde-like products,and the hydrolysis experiment of BDNPP with a rate con-stant k_(obs)of 5.3×10~(-6)s~(-1).     

4, 5-二氮芴-9-酮Cu(II)、Co(II)多核配合物的合成，晶体结构及DNA结合作用初探

合成了两个4, 5-二氮芴-9-酮Cu(II)、Co(II)的多核配合物[Cu2(CH3COO)4(H2O) 2]·2dafo 1 和 [(μ2-O)2-Co3(dafo)6] (ClO3)2·H2O 2 (dafo=4,5-diazafluoren-9-one) 并且对它们进行了元素分析,红外以及紫外光谱的表征,同时测定了配合物的晶体结构。用紫外光谱,发射光谱和循环伏安三种方法初步研究了配合物1和2与DNA的结合作用,结果表明,配合物1和2与DNA的结合为以插入作用为主 。     

Na3[Tb(C4H4O5)3]·2NaClO4·6H2O晶体的偏振发光光谱的配位场分析

以双层点电荷配位场(DSCPCF)模型和不可约张量算符方法,用自编程序计算了三角对称TbODA晶体的配位场微扰能级,并对其偏振荧光光谱进行了理论归属,结果与实验相一致.与经典点电荷配位场(PCF)模型的计算结果相比,DSCPCF模型更符合实际.     

水溶性[5-邻(乙氧羰基甲氧基苯基)-10,15,20-Tri(4-N-甲基吡啶基)]卟啉铜(Ⅱ)配合物的合成、表征及其和单核苷酸的相互作用

合成并表征了 [5- o-(乙氧羰基甲氧基苯基 )-10,15,20-Tri(4-N-甲基吡啶基 )]卟啉 H_2[（ 5-o- (Emoph)-Tri(4-N- Mepy)]PP(1)及其铜配合物 Cu[（ 5- o- (Emoph)-Tri(4- N- Mepy)]PP(2),用紫外可见光谱滴定法测定了配合物 (2)与单核苷酸的配位平衡常数,研究了它作为主体分子和单核苷酸的相互作用。研究结果表明,各配体结合常数按 K(dGMP) >K(dAMP) >K(dTMP) >K(dCMP)≥ K(dUMP)的顺序依次减小。测定了π-π配合反应的Δ_rG,Δ_rH,Δ_rS,发现该反应是放热,熵减小的过程,该反应体系存在焓熵补偿关系。     

用荧光猝灭和荧光加强两种理论研究喹诺酮类新药与白蛋白的作用

应用荧光加强和荧光猝灭两种理论公式, 对四种喹诺酮类药物与人血清和牛血清白蛋白的作用作进行了对比研究, 对药物与白蛋白的结合特点和通常的表征量(解离常数、 猝灭常数、 猝灭效率、 能量转移效率、 给体 受体作用距离等)进行了深入地分析; 在白蛋白与药物结合类型上, 四种药物对HSA和BSA的猝灭实验结果表明, 这种由给体-受体结合引起的猝灭作用类型不是由生物大分子血清白蛋白单方面决定的, 而是由血清白蛋白与药物、 即给体与受体两者的分子结构和相互匹配共同决定的.