A Schiff base ligand N-(2-hydroxylacetophenone)-3-oxapentane-1,5-diamine and its nickel(II) complex: synthesis, crystal structure, antioxidation, and DNA-binding properties

Abstract

A new Schiff base ligand N-(2-hydroxylacetophenone)-3-oxapentane-1,5-diamine (HL) and its Ni complex, [Ni 2 (L) 2 (NO 3 ) 2 ], have been synthesized and characterized by physicochemical and spectroscopic methods. The X-ray crystal structure of [Ni 2 (L) 2 (NO 3 ) 2 ] shows it to be a dinuclear 2:2 complex, in which each Ni(II) atom is in a distorted octahedral geometry. The two Ni(II) atoms are dibridged by two phenoxo ligands, forming a Ni 2 O 2 parallelogram-type moiety. The interactions between free HL and the complex with calf thymus DNA have been investigated, and the binding constant and linear Stern-Volmer quenching constant suggest that the two compounds bind to DNA via the intercalation mode. The binding affinity of the complex was higher than that of HL. Antioxidant assays in vitro showed that the Ni(II) complex possesses significant antioxidant activity.

Schiff Bases: A Versatile Pharmacophore

“…According to the results the 50% inhibitory concentration (IC 50 ) value of 33 was found to be 8.1 ± 0.078 M whereas IC 50 for mannitol was 9.6 M and 32 was devoid of antioxidant activity. Both 32 and 33 bind to DNA in intercalation mode but the binding strength of 33 was found to be better than 32 [49].…”

Studying non-covalent drug–DNA interactions

“…This assay is very commonly used to differentiate between the binding modes. Ethidium bromide (EB) is extensively used as a fluorescence probe that binds to DNA in an intercalative fashion [35][36][37][38][39]. The fluorescence of EB increases when it gets intercalated between DNA base pairs.…”

Crystal structure of diaqua-bis(N,N-dimethylformamide-κ1 O)-bis{3-((5-chloro-2-oxidobenzylidene)amino)-2-oxo-2H-chromen-4-olato-κ4 N,O,O′:O′}dinickel(II), C38H34Ni2Cl2N4O12

“…These schiff base ligands and their metal complexes could be utilized in obtaining luminescence materials [7][8][9][10], biological systems [11,12], magnetic materials [13][14][15], and supramolecular constructing [16,17] figure). The coordination geometry of the Ni(II) centers can be described as slightly distorted octahedra with axial donor atoms (O5 and O6).…”