title: Synthesis, molecular structure, biological properties and molecular docking studies on Mn(II), Co(II) and Zn(II) complexes containing bipyridine-azide ligands.
abstract: Metal complexes of the type Mn(bpy)2(N3)2 (1), Co(bpy)2(N3)2·3H2O (2) and Zn2(bpy)2(N3)4 (3) (Where bpy = 2,2-bipyridine) have been synthesized and characterized by elemental analysis and spectral (FT-IR, UV-vis) studies. The structure of complexes (1-3) have been determined by single crystal X-ray diffraction studies and the configuration of ligand-coordinated metal(II) ion was well described as distorted octahedral coordination geometry for Mn(II), Co(II) and distorted square pyramidal geometry for Zn(II) complexes. DNA binding interaction of these complexes (1-3) were investigated by UV-vis absorption, fluorescence circular dichroism spectral and molecular docking studies. The intrinsic binding constants Kb of complexes 1, 2 and 3 with CT-DNA obtained from UV-vis absorption studies were 8.37 × 10(4), 2.23 × 10(5) and 5.52 × 10(4) M(-1) respectively. The results indicated that the three complexes are able to bind to DNA with different binding affinity, in the order 2 > 1 > 3. Complexes (1-3) exhibit a good binding propensity to bovine serum albumin (BSA) proteins having relatively high binding constant values. Gel electrophoresis assay demonstrated the ability of the complexes 1-3 promote the cleavage ability of the pBR322 plasmid DNA in the presence of the reducing agent 3-mercaptopropionic acid (MPA) but with different cleavage mechanisms: the complex 3 cleaves DNA via hydrolytic pathway (T4 DNA ligase assay), while the DNA cleavage by complexes 1 and 2 follows oxidative pathway. The chemical nuclease activity follows the order: 2 > 1 > 3. The effects of various activators were also investigated and the nuclease activity efficacy followed the order MPA > GSH > H2O2 > Asc. The cytotoxicity studies of complexes 1-3 were tested in vitro on breast cancer cell line (MCF-7) and they found to be active.
authors.affiliation: Department of Industrial Chemsitry, Karaikudi 630003, Tamilnadu, India.
authors.forename: Vijayan
authors.initials: V
authors.lastname: Thamilarasan
authors.affiliation: Department of Industrial Chemsitry, Karaikudi 630003, Tamilnadu, India.
authors.forename: Arumugam
authors.initials: A
authors.lastname: Jayamani
authors.affiliation: DDE, Alagappa University, Karaikudi 630003, Tamilnadu, India. Electronic address: nsvelan1975@yahoo.com.
authors.forename: Nallathambi
authors.initials: N
authors.lastname: Sengottuvelan
mesh_terms: D015082:2,2'-Dipyridyl / Q000737:chemistry*; D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D001386:Azides / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D003035:Cobalt / Q000737:chemistry*; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D053837:DNA Cleavage / Q000187:drug effects; D004278:DNA, Superhelical / Q000187:drug effects; D055808:Drug Discovery; D061986:MCF-7 Cells; D008345:Manganese / Q000737:chemistry*; D062105:Molecular Docking Simulation; D011485:Protein Binding; D012710:Serum Albumin, Bovine / Q000378:metabolism; D014961:X-Ray Diffraction; D015032:Zinc / Q000737:chemistry*
chemical_list: D000970:Antineoplastic Agents; D001386:Azides; D056831:Coordination Complexes; D004278:DNA, Superhelical; D012710:Serum Albumin, Bovine; D003035:Cobalt; D008345:Manganese; D015082:2,2'-Dipyridyl; D015032:Zinc
keywords: Bovine serum albumin; Cobalt(II) and Zinc(II) complexes; Cytotoxic activity; DNA binding and cleavage activity; Manganese(II); Molecular docking; X-ray crystal structure