Pyrazolate as bridging ligand in stabilization of self-assemble Cu(II) Schiff base complexes: Synthesis, structural investigations, DNA/protein (BSA) binding and growth inhibitory effects on the MCF7, CT-26, MDA-MB-231 cell lines

Abstract

Two copper (II) complexes [Cu4(L)2(µ-pz)2] (C1) (L = N,N′-bis(salicylidene)-1,3-diamino-2-propanol; pz = pyrazolate) and [Cu2(Lʹ)(µ-pz)] (C2) (Lʹ = 2,6-bis-(2-hydroxyphenylimino)-4-methylphenol) were synthesized and characterized by elemental analysis, UV–Vis and IR spectroscopy. Also C1 characterized by single crystal X-ray crystallography. The crystal structure of C1 consists of tetranuclear species, in which the alkoxo oxygen as endogenous bridging atom of a dinuclear species contacts to the Cu2 center of the other dinuclear species. The interactions of both complexes with Fish Sperm DNA (FS-DNA) was investigated by UV–Vis and fluorescence spectroscopy as well as viscosity measurements, cyclic voltammetry (CV), circular dichroism (CD), docking studies and agarose gel electrophoresis. Moreover, the interaction of these complexes with BSA was investigated by fluorescence and UV–Vis spectroscopy, circular dichroism (CD) and docking studies. In addition, growth inhibitory effects of the synthesized complexes were assayed by MTT assay on the MCF-7 (breast carcinoma), MDA-MB-231 (breast carcinoma) and CT-26 (colon carcinoma) cell lines.