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早期的工作表明很多亲核试剂可以置换trans-[en2Os(η2-H2)D2O]2+(称其为探针)中的D2O,导致其特征H2的1H NMR负区化学位移发生变化. 如果亲核试剂与探针的键合常数可以测得, 则它与其他金属离子的键合常数也可方便地求出. 运用此探针以竞争模式系统研究了 Cp2TiCl2,R2SnCl2, 抗癌药物顺铂等与 dGMP 之间的作用, 详细诠释了它们的竞争键合、组分变化、键合常数之间的定量关系, 论述了不同药剂与 dGMP 结合的差异. 结果表明, 在探针与 dGMP 的体系中加入药物后, 药物和探针对 dGMP 的咪唑氮 N7和磷酸氧两个位点进行竞争结合. 对于 Cp2TiCl2,Ti 与磷酸氧、咪唑氮均有明显的结合; 而(CH3)2SnCl2 与 dGMP 的磷酸氧有明显键合, 与咪唑氮则甚少结合. 探针与 N7 的键合将导致它对同一 dGMP 分子上磷酸氧的键合能力减弱. 研究这些抗肿瘤金属络合物与单核苷酸、尤其是 DNA 的基本单元 dGMP 之间的作用, 对于阐明络合物与DNA 键合模式是重要的. 预期这一结论同样适用于其他金属络合物与核苷酸的键合.
Earlier work showed that many nucleophiles could displace D2O in trans- [en2Os (η2-H2) D2O] 2+ (call it a probe), resulting in a change in the chemical shift of the 1H NMR negative region of its characteristic H2 If the pro The binding constant between the nucleus reagent and the probe can be measured, and the bond constant between the reagent and other metal ions can also be easily determined.Using this probe, Cp2TiCl2, R2SnCl2 and cisplatin And dGMP, the quantitative relationship between their competitive binding, component changes and bonding constants is explained in detail, and the differences between the binding of different drugs and dGMP are discussed.The results show that in the system of probe and dGMP After addition of the drug, the drug and the probe competitively bind to both sites of imidazole nitrogen N7 and phosphate oxygen of dGMP. For Cp2TiCl2, Ti is obviously bound to phosphate oxygen and imidazole nitrogen; and (CH3) 2SnCl2 and dGMP phosphoric acid Oxygen has a significant bond, and very few with imidazole nitrogen binding probe N7 will result in its binding to the same dGMP molecular oxygen phosphate weakening of these anti-tumor metal complexes and single nucleotide , In particular the basic unit of DNA, dGMP Is important for elucidating the mode of complexation of DNA with DNA, and this conclusion is expected to be equally applicable to the bonding of other metal complexes to nucleotides.