Crystal structure, chemical nuclease activity, and VHPO mimicking potential of oxovanadium(IV) complexes—A combined experimental and computational study

Abstract

A series of oxovanadium(IV) complexes [VO(salala)(phen)] (1), [VO(salala)(bpy)] (2), and [VO(napala)(phen)] (3) where salala and napala are N‐salicylidene‐β‐alanate and N‐napthalidene‐β‐alanate, respectively, and phen = 1,10‐phenanthroline and bpy = 2,2′‐bipyridine have been synthesized. The single‐crystal X‐ray crystallographic data of complex 2 reveal that its crystal structure exists in the monoclinic space group P21/a. All the complexes adopted distorted octahedral geometry and are confirmed through various spectral techniques including FTIR, UV–Vis, ESI mass, EPR, molar conductance, and magnetic measurements. To gain insights into the electronic structure of these synthesized complexes, density functional theory calculations have been carried out although UV absorption spectra of these complexes are simulated from time‐dependent density functional theory calculations. The cyclic voltammograms reveal the irreversible and the one‐electron transfer process of the complexes. The chemical nuclease activity of the complexes has also been done on pUC19 DNA. The results show that complex 2 acts as an excellent enzyme mimic of vanadium‐dependent bromoperoxidase involving in the effective bromination of phenol red at room temperature in acetonitrile medium. So investigation on the vanadium complex catalyzed conversion of organic substrates to corresponding brominated products has been a field of active research and found that the complex is certainly a VHPO mimic.

Cytotoxic and mechanistic studies of novel phenanthroline-derived oxovanadium(IV) complexes.

“…2,21,34,113,167,171,211,215,217,218,241 have been reported to have antidiabetic, 45,221,225,226,269 antiparasitic, 36,100,240,247,248 antitumour 2,21,34,36,38,100,150,167,242,250 and catalytic properties. 189,252,261,268,273,279,282,286 Figures 1.15 (e), (j) and Figures 1.16 (h) -(k) have also been determined to bind to bovine serum albumin. 113,216,241 Studies on the interactions of transition metal complexes with bovine serum albumin are important as serum albumins are the most abundant proteins in blood and have the ability to transport and deposit drugs.…”

“…In oxidative cleavage, oxidation of deoxyribose sugars occurs through removal of a sugar hydrogen atom, or DNA nucleobases are oxidised by reactive oxygen species (ROS). 42,99,181,189 ROS such as singlet oxygen, superoxide, and hydroxyl radicals are generated through external co-reactants such as reducing or oxidising agents, for example, peroxide. 181 Peroxide can form in living systems through reduction of oxygen in the respiration chain, reduction of superoxide or dimerisation of hydroxyl radicals.…”

“…Numerous oxovanadium(IV) complexes of N,N-bidentate polypyridyl-derived and O,N,Sdonor 20,27,40,41,63,149,162,171,173,174,188,215,[243][244][245][246] or O,N,O´-donor 2,21,26,[34][35][36]38,43,45,100,113,127,150,165,167,176,178,189,[211][212][213][216][217][218][219]221,[225][226][227]237,238,[240][241][242] Schiff base ligands have been reported. Ternary…”