Butler J, Hoey B M, Swallow A J
Radiat Res. 1985 Apr;102(1):1-13.
Oxidation and reduction of cis- and trans-dichlorodiammine platinum II (cis- and trans-PDD), cis-dichlorobis(1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole-N3)-p latinum II (cis-Flap), and cis-dichlorobis(isopropylamine)-trans-dihydroxyplatinum IV (Chip) have been studied using pulse radiolysis. Spectra corresponding to platinum in various oxidation states have been observed and several rate constants have been obtained. Reduction of all the compounds, except cis-Flap, produces species of a lower oxidation state of platinum which subsequently have both chloride ligands replaced. Ultimately, these products disproportionate. In the case of cis-Flap, reduction occurred on the nitroimidazole ligand. This was verified by the absence of platinum metal after disproportionation. Oxidation of all four compounds consists of production of a higher oxidation state of platinum followed by replacement of chloride ligands and finally disproportionation of the products. Only cis-Flap and Chip could be reduced by oxidized DNA bases. The one-electron reduction potential of cis-Flap was found to be -370 +/- 10 mV. trans-Flap had almost the same value. It was not possible to measure the potentials of the other compounds since their ligands were replaced rapidly but it is estimated that the one-electron reduction potentials decrease in the order cis- or trans-Flap greater than Chip greater than cis-PDD greater than trans-PDD.
已使用脉冲辐解研究了顺式和反式二氯二氨合铂（II）（顺铂和反铂）、顺式二氯双（1-(2-羟乙基)-2-甲基-5-硝基咪唑-N3）铂（II）（顺式-Flap）和顺式二氯双（异丙胺）-反式二羟基铂（IV）（Chip）的氧化和还原过程。观察到了对应于各种氧化态铂的光谱，并获得了几个速率常数。除顺式-Flap外，所有化合物的还原都会产生铂较低氧化态的物种，随后这两种氯化物配体都会被取代。最终，这些产物会发生歧化反应。对于顺式-Flap，还原发生在硝基咪唑配体上。歧化反应后没有铂金属这一现象证实了这一点。所有四种化合物的氧化过程包括产生铂的较高氧化态，随后氯化物配体被取代，最终产物发生歧化反应。只有顺式-Flap和Chip可以被氧化的DNA碱基还原。发现顺式-Flap的单电子还原电位为-370±10 mV。反式-Flap的值几乎相同。由于其他化合物的配体被迅速取代，因此无法测量它们的电位，但据估计，单电子还原电位按顺式或反式-Flap＞Chip＞顺铂＞反铂的顺序降低。
