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使用质子核磁共振方法测定了新的抗癌活性配合物cis－[Pt（NH3）2（4－mepy）Cl]＋与甲基-谷胱甘肽（GS－Me）的反应及其动力学．结果表明Pt与GS－Me间形成1：1加合物．为了解结合部位，对Pt－GS－Me配合物进行pH滴定，由GS－Me的质子核磁共振谱对pH的依赖关系判断Gs－Me只通过S原子与Pt配位，而氨基和羧基不参与配位反应．由配体吡啶环质子核磁共振随时间的变化，提出了两步反应机制：首先GS－Me通过S原子与Pt配位，然后由于S配位的高度反位效应使反应的NH3活动化．通过1HNMR方法测定了第一步反应的速率常数k＝0．017L·mol－1·s－1（pH3．1）和k＝0．013L·mol－1·s－1（pH7．2）．
The reaction and kinetics of the novel antitumor complex cis- [Pt (NH3) 2 (4-mepy) Cl] + with methyl-glutathione (GS-Me) were determined by proton NMR. The results show that Pt and GS-Me form a 1: 1 adduct. In order to understand the binding sites, pH-titration of Pt-GS-Me complexes was carried out. The dependence of pH on the proton nuclear magnetic resonance spectrum of GS-Me determined that Gs-Me only coordinated to Pt through S atoms, while the amino and carboxyl groups did not participate Coordination reaction. The two-step reaction mechanism is proposed by the change of the proton nuclear magnetic resonance of the pyridine ring with time. First, GS-Me coordinates with Pt through the S atom, and then NH3 is activated due to the highly anti-site effect of S coordination. The rate constant k = 0.017L · mol-1 · s-1 (pH3.1) and k = 0.013L · mol-1 · s-1 (pH7.2) of the first reaction were determined by 1HNMR method.