A new blue luminescent dichlorido-bridged dinuclear copper(II) complex with DNA binding and cytotoxic activities: Synthesis, structure and DFT studies

作者：Mukherjee Soma^*; Basu Chandrama; Chowdhury Santanu; Chattopadhyay Asoke P; Ghorai Atanu; Ghosh Utpal; Stoeckli Evans Helen

来源：Inorganica Chimica Acta, 2010, 363(12): 2752-2761.

DOI：10.1016/j.ica.2010.04.026

• Luminescence
• Dinuclear copper(II) complex
• Structure
• DFT and TDDFT
• DNA binding
• Cytotoxicity

A blue luminescent dichlorido-bridged dinuclear copper(II) (S = 1/2) complex, [Cu(2)(II)(HL)(2)(mu-Cl)(2)]center dot 2H(2)O, 1a was synthesized with the 1:1 reaction of the acyclic tridentate salicylaldehyde 2-pyridyl hydrazone ligand, HL, 1. The complex 1a displays multiple bands in the visible region (400-470 nm). The association constant (K(ass), UV-Vis) was found to be 1.186 x 10(4) for 1a at 298 K. The copper(II)-copper(III) oxidation potential lies near 0.32 V versus Ag/AgCl electrode. On excitation at 390 nm, the ligand 1 strongly emits at 444 nm due to an intraligand (1)(pi-pi*) transition. Upon complexation with copper(II) the emission peak is slightly red shifted (lambda(ex) 390 nm, lambda(em) 450 nm, F/F(0) 0.81) with little quenching. Molecular structure of 1a (Cu ... Cu 3.523 angstrom) has been determined by single crystal X-ray diffraction studies. DFT and TDDFT calculations strongly support the spectral behavior of the ligand and the complex. The complex 1a exhibits a strong interaction towards DNA as revealed from the K(b) (intrinsic binding constant) 2.05 x 104 M (1) and K(sv) (Stern-Volmer quenching constant) 2.47 values. The complex exhibits cytotoxic effect and the LD(50) value for HeLa cells was calculated as 5.44 mu M at which the cell cycle was arrested at G(2)/M phase.

• 出版日期2010-10-15