The Effects of Extending of Co-planarity in a Series of Structurally Relative Polypyridyl Palladium(II) Complexes on DNA-binding and Cytotoxicity Properties

摘要: In depth interaction studies between calf thymus deoxyribonucleic acid (CT-DNA) and a series of four structurally relative palladium(II) complexes [Pd(en)(HB)](NO3)2 (a-d), where en is ethylenediamine heterocyclic base (HB) 2,2'-bipyridine (bpy, a); 1,10-phenanthroline (phen, b); dipyridoquinoxaline (dpq, c) dipyridophenazine (dppz, d) (Figure 1), were performed. These have been investigated by utilizing the electronic absorption spectroscopy, fluorescence spectra ethidium bromide (EBr) displacement gel filtration techniques. a-d cooperatively bind denature DNA at low concentrations. Their concentration midpoint transition, L1/2, follows order >> b > c d. Also g, number binding sites per 1000 nucleotides, ~ EBr Scatchard experiments for suggest efficient intercalative affinity to CT-DNA giving order: d a. Several thermodynamic parameters are also described. The biological activity these cationic water soluble palladium tested against chronic myelogenous leukemia cell line, K562. b, show cytotoxic (Cc50) values much lower than cisplatin.