Synthesis, characterization and biological activity of new cyclometallated platinum(iv) iodido complexes

Autor: Bauer E, Domingo X, Balcells C, Polat IH, Crespo M, Quirante J, Badia J, Baldoma L, Font-Bardia M, Cascante M
Rok vydání: 2017
Zdroj: DALTON TRANSACTIONS
r-FSJD: Repositorio Institucional de Producción Científica de la Fundació Sant Joan de Déu
Fundació Sant Joan de Déu
r-FSJD. Repositorio Institucional de Producción Científica de la Fundació Sant Joan de Déu
instname
ISSN: 1477-9226
Popis: The synthesis of six novel cyclometallated platinum(iv) iodido complexes is accomplished by intermolecular oxidative addition of methyl iodide (compounds 2a-2c) or iodine (compounds 3a-3c) upon cyclometallated platinum(ii) compounds [PtX{(CH 3 ) 2 N(CH 2 ) 3 NCH(4-ClC 6 H 3 )}] (1a-1c: X = Cl, CH 3 or I). The X-ray molecular structures of platinum(ii) compound 1c and platinum(iv) compounds 3b and 3a' (an isomer of 3a) are reported. The cytotoxic activity against a panel of human adenocarcinoma cell lines (A-549 lung, MDA-MB-231 and MCF-7 breast, and HCT-116 colon), DNA interaction, topoisomerase I, IIa, and cathepsin B inhibition, and cell cycle arrest, apoptosis and ROS generation of the investigated complexes are presented. Remarkable antiproliferative activity was observed for most of the synthesized cycloplatinated compounds (series 1-3) in all the selected carcinoma cell lines. The best inhibition was provided for the octahedral platinum(iv) compounds 2a-2c exhibiting a methyl and an iodido axial ligand. Preliminary biological results point to a different mechanism of action for the investigated compounds. Cyclometallated platinum(ii) compounds 1a-1c modify the DNA migration as cisplatin. In contrast, cyclometallated platinum(iv) compounds 2a-2c and 3a-3c did not modify the DNA tertiary structure neither in the absence nor in the presence of ascorbic acid, which made them incapable of reducing platinum(iv) compounds 2b and 2c in a buffered aqueous medium (pH 7.40) according to 1 H NMR experiments. Remarkable topoisomerase IIa inhibitory activity is reported for platinum(iv) complexes 2b and 3a and in addition, for the last one, a moderate cathepsin B inhibition is reported. Cell cycle arrest (decrease in G0/G1 and G2 phases and arrest in the S phase), induction of apoptosis and ROS generation are related to the antiproliferative activity of some representative octahedral cyclometallated platinum(iv) compounds (2b and 2c).
Databáze: OpenAIRE