ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesis, structural characterization, thermal analysis, DFT, biocidal evaluation and molecular docking studies of amide-based Co(II) complexes

Subhash, Ashu Chaudhary, Mamta, and Jyoti

Department of Chemistry, Kurukshetra University, Kurukshetra, India

E-mail: ashuchaudhary@kuk.ac.in

Received: 20 January 2023  Accepted: 21 April 2023

Abstract:

Abstract

Many distinct amino acid and aromatic amine-derived transition metal complexes are used as physiologically active compounds. A few Cobalt (II) complexes have been synthesized by reacting cobalt (II) chloride with 1, 8-diaminonapthalene-based tetraamide macrocyclic ligands in an ethanolic media. These synthesized ligands (TAML_1-3) and associated Co(II) complexes were fully characterized with various spectroscopic techniques, such as IR, NMR, CHN analysis, EPR, molar conductance, and magnetic susceptibility measurements, TGA, UV–visible spectra, powder X-ray diffraction and DFT analysis. The IR spectra reveal interactions between the core metal atom and ligands through N of 1, 8-diaminonapthalene. The distorted octahedral geometry of synthesized Co(II) macrocyclic complexes were confirmed by ESR, UV–Vis and DFT studies. The synthesized ligands (TAML₁-TAML₃) and their Co(II) complexes were tested for antimicrobial activity against A. niger, C. albicans, and F. oxysporum in addition to bacteria like S. aureus, B. subtilis, and Gram-negative bacteria like E. coli. The ligand TAML₁ and complex [Co(TAML₁)Cl₂] showed an excellent antibacterial activity. The minimum inhibitory concentration of TAML₁ and [Co(TAML₁)Cl₂] against S. aureus were found to be 7 mm and 10 mm zone of inhibition at 500 ppm, respectively, compared to drug ampicillin (3 mm). Additionally, each molecule exhibited notable antioxidant activity. The biological significance of the synthesized compounds was then evaluated by molecular docking experiments with the active site of the receptor protein such as Sars-Cov-2, C. Albicans, X. campestris and E. coli. The molecular docking assisted data strongly correlated to the experimental approach of antimicrobial activity.

Graphical Abstract

Keywords: Antimicrobial; DFT investigation; Docking studies; Macrocyclic ligands; Thermal analysis

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-02843-y

Chemical Papers 77 (9) 5059–5078 (2023)