Synthesis, characterization, and antifungal and antioxidant evaluation of novel ethylenediamine-derived Schiff bases and their Ni(II), Co(II), Cd(II), and Cu(II) complexes

Authors

  • P. D. Iorungwa
    Department of Chemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria
  • M. S. Iorungwa
    Department of Chemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria
  • S. D. Umoh
    Department of Chemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria
  • R. A. Wuana
    Department of Chemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria
  • E. N. Iornumbe
    Department of Chemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria
  • A. G. Ugama
    Department of Chemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria
  • L. T. Tyagher
    Department of Chemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria

Keywords:

Antifungal activity, Antioxidant activity, Schiff base complexes, Spectroscopic characterization, Transition metal complexes

Abstract

Three Schiff base ligands derived from condensation of ethylenediamine with benzaldehyde, salicylaldehyde, and vanillin, namely (1E,1'E)-N,N'-(ethane-1,2-diyl)bis(1-phenylmethanimine) (BBE), 4,4'-((1E,1'E)-(ethane-1,2-diylbis(azaneylylidene))bis(methaneylylidene))bis(2-methoxyphenol) (BHE), and 2,2'-((1E,1'E)-(ethane-1,2-diylbis(azaneylylidene))bis(methaneylylidene))diphenol (BME), were synthesized and complexed with Co(II), Cu(II), Ni(II), and Cd(II) ions. To the best of our knowledge, these specific metal complexes have not been reported previously, and their biological activities have not been evaluated. The ligands and complexes were characterized by melting point determination, solubility tests, molar conductivity, UV--visible and FTIR spectroscopy, magnetic susceptibility, X-ray fluorescence, powder X-ray diffraction (XRD), and thermogravimetric/differential thermal analyses (TGA/DTA). Low molar conductivity values (10.5--12.0 Omega-1 cm2 mol-1) indicate non-electrolytic behavior, while FTIR and X-ray fluorescence studies indicate coordination through azomethine nitrogen and oxygen donor atoms. XRD patterns show crystalline structures with sharp diffraction peaks, and thermal analyses indicate multistep decomposition and good thermal stability. Biological analysis indicates increased antifungal activity of the metal complexes over the free ligands, with lower minimum inhibitory concentrations; some complexes also showed improved 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (IC50 = 0.68101 mg/mL). The first-row transition metals are biologically relevant, while Cd(II) was included only for comparative structure--activity evaluation despite its known toxicity. This study provides insight into Ni(II) and Cd(II) complexes through integrated structural, thermal, and biological characterization.

Dimensions

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FIG5

Published

2026-09-08

How to Cite

Synthesis, characterization, and antifungal and antioxidant evaluation of novel ethylenediamine-derived Schiff bases and their Ni(II), Co(II), Cd(II), and Cu(II) complexes. (2026). Journal of the Nigerian Society of Physical Sciences, 8(4), 3425. https://doi.org/10.46481/jnsps.2026.3425

Issue

Volume 8, Issue 4, November 2026 (in progress)

Section

Chemistry
Copyright & Licensing

Copyright (c) 2026 P. D. Iorungwa, M. S. Iorungwa, S. D. Umoh, R. A. Wuana, E. N. Iornumbe, A. G. Ugama, L. T. Tyagher (Author)

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

Synthesis, characterization, and antifungal and antioxidant evaluation of novel ethylenediamine-derived Schiff bases and their Ni(II), Co(II), Cd(II), and Cu(II) complexes. (2026). Journal of the Nigerian Society of Physical Sciences, 8(4), 3425. https://doi.org/10.46481/jnsps.2026.3425

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