Research Article Oxoperoxovanadium Complexes of Hetero Ligands: X-Ray Crystal Structure, Density Functional Theory, and Investigations on DNA/ BSA Interactions, Cytotoxic, and Molecular Docking Studies Saraswathi Kothandan, 1 Krishnan Thirumoorthy, 1 Antonio Rodr´ ıguez-Di´ eguez, 2 and Angappan Sheela 1 1 Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore-632014, India 2 Department of Inorganic Chemistry, Faculty of Science, University of Granada, Av/Severo Ochoa s/n, Granada 18071, Spain Correspondence should be addressed to Angappan Sheela; asheela@vit.ac.in Received 18 April 2022; Revised 17 June 2022; Accepted 6 July 2022; Published 17 August 2022 Academic Editor: Anastasios Keramidas Copyright © 2022 Saraswathi Kothandan et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Oxoperoxovanadium (V) complexes [VO (O) 2 (nf) (bp)] ( 1) and [VO (O) 2 (ox) (bp)] (2) based on 5-nitro-2-furoic acid (nf ), oxine (ox) and 2, 2′ bipyridine (bp) bidentate ligands have been synthesized and characterized by FT-IR, UV-visible, mass, and NMR spectroscopic techniques. e structure of complex 2 shows distorted pentagonal-bipyramidal geometry, as confirmed by a single-crystal XRD diffraction study. e interactions of complexes with bovine serum albumin (BSA) and calf thymus DNA (CT- DNA) are investigated using UV-visible and fluorescence spectroscopic techniques. It has been observed that CT-DNA interacts with complexes through groove binding mode and the binding constants for complexes 1 and 2 are 8.7 × 10 3 M -1 and 8.6 × 10 3 M -1 , respectively, and BSA quenching constants for complexes 1 and 2 are 0.0628 × 10 6 M -1 and 0.0163 × 10 6 M -1 , respectively. e ability of complexes to cleave DNA is investigated using the gel electrophoresis method with pBR322 plasmid DNA. Furthermore, the cytotoxic effect of the complexes is evaluated against the HeLa cell line using an MTT assay. e complexes are subjected to density functional theory calculations to gain insight into their molecular geometries and are in accordance with the results of docking studies. Furthermore, based on molecular docking studies, the intermolecular interactions responsible for the stronger binding affinities between metal complexes and DNA are discussed. 1. Introduction DNA interaction studies are the active research area at the interface of biology and chemistry and play a key role in the development of new anticancer medicines [1–3]. Small molecules bind through covalent and noncovalent modes of binding and bring about hydrolytic, oxidative, and photo- lytic cleavage of DNA. It interferes with the replication and transcription processes responsible for cell death [4]. Serum albumin is the main protein in the blood plasma and it plays a significant role in drug pharmacokinetics and pharma- codynamics [5, 6]. Because of its capacity to bind reversibly to a wide range of molecules, it is considered the major transporter of regulatory mediators, metabolic products, nutrients, and fatty acids. rough hydrogen bonding, hy- drophobic, and electrostatic interactions, serum albumin neutralizes endogenous and external poisons [7, 8]. Several metal complexes are known to exert their anticancer action through effective binding with nucleases and proteins. In this context, vanadium complexes have been thoroughly studied for their binding efficacies with DNA and BSA. Vanadium forms complexes with many organic molecules and is advantageous over vanadium salts with lesser toxic effects and exerts greater biological efficacy at a very low dosage level. In bioinorganic chemistry, their compounds play a significant role in several enzyme-related biochemi- cal responses like stimulating the functions of myosine ATPase, adenylate kinase, choline esterase, dynein, and Hindawi Bioinorganic Chemistry and Applications Volume 2022, Article ID 8696420, 15 pages https://doi.org/10.1155/2022/8696420