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

• Published in: Applied organometallic chemistry 2021-02, Vol.35 (2), p.n/a
• Main Authors: Bennie, R. Biju, Livingston, D. Jim, Joel, C., Jeyanthi, D., Solomon, Rajadurai Vijay
• Format: Article
• Language: English
• Subjects: Absorption spectra; Acetonitrile; Bromination; Chemical activity; chemical nuclease activity; Chemistry; Crystal structure; Crystallography; Density functional theory; Electron transfer; Electronic structure; Magnetic measurement; Mathematical analysis; Nuclease; oxovanadium(IV) complexes; Resistance; Room temperature; Substrates; Synthesis; TDDFT; Vanadium; VHPO
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.6106

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. A series of oxovanadium(IV) complexes have been synthesized from Schiff base of amino acids with heterocyclic base. The structure of the complex [VO(salala)Bpy] have been deduced by X‐ray crystal analysis. DFT calculations were used for the optimization of the complexes at B3LYP level. The chemical nuclease activity of the complexes was studied by agarose gel electrophoresis method using pUC19 DNA. The VHPO mimicking activity of complex 2 was studied on the bromination of phenol red to bromophenol blue.