Wydział Chemii

Henryk Chojnacki

Janina Kuduk-Jaworska

Iwona Jaroszewicz

Jerzy Jański

2009

Polish Journal of Chemistry

83

1013-1024

Naukowa

Angielski

Artykuł

The motivation to this work results from the recognition of cis-dia mminedi - chloroplatinum(II) (cisplatin) hydration processes as essential for the fate of this drug in host organism. Applying quantum chemical calculations, there were evaluated the first stages of water molecule impact on platinum complexes: cisplatin and its trans isomer. Non-empirical quantum chemical calculations have been performed for reactions of cisand trans-diamminedichloroplatinum(II) (transplatin) with the water molecule, as sum - ing the associative mode of reactions running with the addition of a fifth ligand to a square planar d8 complex and formation of a trigonal-bipyramidal structure of the transition state. For the obtained structures of reactants, transition states, and products, the ther mo - dynamic characteristics (energies and Gibbs free energies) were estimated. Energetics for the ligand exchange reactions were estimated both in gas phase and water solution by using the PCM model. The hydration reactions under consideration are principally endothermic except of the solvated transplatin. Basing on our ab in itio ZORA calculations, the possible role of relativistic effects in the reaction mechanism is pointed out as well. Ob - tained results may throw some light on processes which determine the inter change of pro-drug (cisplatin) into activated drug (aqua-form) and implicate their significance in de signing of anticancer, Pt-containing chemotherapeutics.

cisplatin, transplatin, interactions with water molecule, quantum mechanical calculation, relativistic ZORA calculations