caa a22 4500 378871188 CHVBK 20180305123409.0 cr unu---uuuuu 161128e20030101xx s 000 0 eng 10.1515/irm-2003-0108 doi (NATIONALLICENCE)gruyter-10.1515/irm-2003-0108 Substitution of aqua ligands from ds-[Pt(en)(H2O)2](ClO4)2 and cis-[Pt(dmen)(H2O)2](ClO4)2 (en [Elektronische Daten] ethylenediamine, dmen = Ν,Ν′-dimethylethylenediamine) by glutathione (reduced) (GSH) in aqueous medium - A Kinetic And Mechanistic Study [S. K. Bera, P. S. Sengupta, G. S. De] The kinetics of the interaction of glutathione (reduced) (GSH) with [Pt(en)(H2O)2](ClO4)2and [Pt(dmen)(H2O)2](ClO4)2 (en = ethylenediamine, dmen = N,N'-dimethylethylenediamine) have been studied spectrophotometrically as a function of [substrate complex], [glutathione] and temperature at a particular pH (4.0). The reaction was found to proceed via rapid outersphere association complex formation followed by two slow consecutive steps. The first step involves the transformation of the outersphere complex into the innersphere complex containing Pt-S bond, while the second step involves chelation when the second aqua ligand is displaced. The association equlibrium constant (KE) and the two rate constants k1 and k2 have been evaluated. Activation parameters for both the steps have been calculated using Eyring equation. The low enthalpy of activation and large negative values of entropy of activation indicate an associative mode of activation for both steps. © 2014 by Walter de Gruyter Berlin/Boston Kinetics nationallicence substitution nationallicence glutathione nationallicence Platinum nationallicence Pt(ll) nationallicence dmen nationallicence en nationallicence Bera S. K. aut Sengupta P. S. aut De G. S. aut BioInorganic Reaction Mechanisms De Gruyter 5/1(2003-01-01), 65-72 2191-2483 5:1<65 2003 5 irm https://doi.org/10.1515/irm-2003-0108 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1515/irm-2003-0108 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bera S. K. aut NATIONALLICENCE 700 1- Sengupta P. S. aut NATIONALLICENCE 700 1- De G. S. aut NATIONALLICENCE 773 0- BioInorganic Reaction Mechanisms De Gruyter 5/1(2003-01-01), 65-72 2191-2483 5:1<65 2003 5 irm CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter