Synthesis, Spectroscopic Studies and Biological Activity of Cu(II) Complex of Schiff Base Ligand 3-((2-(2,4-dinitrophenyl)hydrazineylidene)methyl)pyridine with Triphenylphosphine as Ancillary Ligand

Authors

Keywords:

Schiff base, Triphenylphosphine, Heteroleptic, Antibacterial-activity, Synergistic

Abstract

In this study we synthesized, characterized, and evaluated the antibacterial activity of a new mixed-ligand Cu(II) complex containing a Schiff base derived from 3-pyridinecarboxaldehyde and 2,4-dinitrophenylhydrazine, together with triphenylphosphine as ancillary ligand. The compound was characterized using Fourier Transform Infrared (FTIR) spectroscopy, UV-Visible spectroscopy, and magnetic susceptibility measurements. Antibacterial screening was carried out using agar well diffusion method against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. FTIR analysis confirmed coordination through the azomethine and pyridyl nitrogen atoms with characteristic bands at 1618 and 1584 cm⁻¹, while retaining nitro group absorptions at 1508 and 1325 cm⁻¹. The complex displayed an average inhibition zone of 26.25 mm, surpassing the standard drug Ofloxacin (23.50 mm) and showing significant enhancement over the free ligands and copper salt. Magnetic susceptibility measurements revealed paramagnetic behaviour. The synthesized heteroleptic Cu(II) complex demonstrated excellent broad-spectrum antibacterial activity, highlighting the synergistic effect of the Schiff base and triphenylphosphine ligands.

Author Biographies

Adejumoke Morilat Hashimi

Department of Chemical Sciences, 

Muritala Adeniyi Olusola

Department of Chemistry, Federal University of Medicine &  Medical Sciences, Abeokuta,Nigeria

Dimensions

Abu-Dief, A. M. and Mohamed, I. M. (2015). A review on versatile applications of transition metal complexes incorporating Schiff bases. Beni-suef university journal of basic and applied sciences, 4(2), 119-133.

Adeleke, A. A., Oladipo, S. D., Zamisa, S. J., Sanusi, I. A. and Omondi, B. (2023). DNA/BSA binding studies and in vitro anticancer and antibacterial studies of isoelectronic Cu (I)-and Ag (I)-pyridinyl Schiff base complexes incorporating triphenylphosphine as co-ligands. Inorganica Chimica Acta, 558, 121760.

Amolegbe, S. A., Adewuyi, S., Akinremi, C. A., Adediji, J. F., Lawal, A., Atayese, A. O. and Obaleye, J. A. (2015). Iron (III) and copper (II) complexes bearing 8-quinolinol with amino-acids mixed ligands: Synthesis, characterization and antibacterial investigation. Arabian Journal of Chemistry, 8(5), 742-747.

Benzerka, S., Bouraiou, A., Bouacida, S., Roisnel, T., Bentchouala, C., Smati, F. and Belfaitah, A. (2012). New 2-phenylquinoline derivatives: Synthesis and preliminary evaluation as antimicrobial agents. Letters in Organic Chemistry, 9(5), 309-313.

Busari, H. K., Obaleye, J. A., Wahab, O. O., Ferjani, H., Vatsha, B., Abolarinwa, T. O., . . . Onwudiwe, D. C. (2026). Zn (II) and Co (II) complexes from binary ligands: Synthesis, characterization, structural insights, DFT analysis and antimicrobial studies. Journal of Molecular Structure, 146173.

Dadgostar, P. (2019). Antimicrobial resistance: implications and costs. Infection and drug resistance, 3903-3910.

Fetoh, A., Asla, K. A., El-Sherif, A. A., El-Didamony, H. and El-Reash, G. M. A. (2019). Synthesis, structural characterization, thermogravimetric, molecular modelling and biological studies of Co (II) and Ni (II) Schiff bases complexes. Journal of Molecular Structure, 1178, 524-537.

Fudulu, A., Olar, R., Maxim, C., Scăeţeanu, G. V., Bleotu, C., Matei, L., . . . Badea, M. (2020). New cobalt (II) complexes with imidazole derivatives: antimicrobial efficiency against planktonic and adherent microbes and in vitro cytotoxicity features. Molecules, 26(1), 55.

Ghaneian, M. T., Tabatabaee, M., Ehrampoush, M. H., Jebali, A., Hekmatimoghaddam, S., Fallahzadeh, H. and Fallahzadeh, R. A. (2015). Synthesis of Ag (I) and Cu (I) complexes with 4-Amino-5-Methyl-2h-1, 2, 4-Triazole-3 (4h)-thione ligand as thiocarbohydrazide derivatives and their antimicrobial activity. Pharmaceutical Chemistry Journal, 49(3), 210-212.

Ghosh, M., Mandal, S., Fleck, M., Saha, R., Rizzoli, C. and Bandyopadhyay, D. (2018). Synthesis, crystal structure, and antimicrobial activity of a series of cobalt (III) Schiff base complexes. Journal of Coordination Chemistry, 71(24), 4180-4193.

Hameed K, S., Meeran I, S. and Askar Ali, S. (2026). Pyridine-Schiff Base Ligand and Metal Complexes: Synthesis, In-silico Modeling, and Structural Insights. Chemistry Africa, 9(3), 152.

Hassan, A. S., Askar, A. A., Nossier, E. S., Naglah, A. M., Moustafa, G. O. and Al-Omar, M. A. (2019). Antibacterial evaluation, in silico characters and molecular docking of Schiff bases derived from 5-aminopyrazoles. Molecules, 24(17), 3130.

Iaroshenko, V. (2019). Organophosphorus chemistry: from molecules to applications: John Wiley & Sons.

Kumah, R. T., Vijayan, P. and Ojwach, S. O. (2021). Synthesis and Applications of (Pyridyl) imine Fe (II) Complexes as Catalysts in Transfer Hydrogenation of Ketones. Catalysis Letters, 151(2), 344-352.

Mahmoud, Z. H., Al-Salman, H., Hussein, U. A.-R., Hameed, S. M., Hussein, A. A., Abbas, J. M., Kianfar, E. (2026). Recent advances in the applications of smart nanomaterials in Biomedicine: A review. Nano Life, 16(03), 2530005.

Mandal, A., Sarkar, A., Adhikary, A., Samanta, D. and Das, D. (2020). Structure and synthesis of copper-based Schiff base and reduced Schiff base complexes: a combined experimental and theoretical investigation of biomimetic catalytic activity. Dalton Transactions, 49(43), 15461-15472.

Moreno-Regino, D., López-Mondragón, A. d. C., Castañeda de la Hoya, F., Hernández-García, F., Márquez-Marín, J., Castanedo-Pérez, R. and Torres-Delgado, G. (2026). Cuprous to cupric oxide phase transformation in thin films deposited by spray pyrolysis subjected to rapid thermal annealing: effect of film thickness on their properties. Emergent Materials, 9(5), 106.

Nakamoto, K. (2009). Infrared and Raman spectra of inorganic and coordination compounds, part B: applications in coordination, organometallic, and bioinorganic chemistry: John Wiley & Sons.

Ngece, K., Khwaza, V., Paca, A. M. and Aderibigbe, B. A. (2025). The antimicrobial efficacy of copper complexes: A review. Antibiotics, 14(5), 516.

Odulaja, O., Adeleke, A., Adewuyi, S., Ibilunle, A., Sanyaolu, N., Yussuf, S. and Hashimi, A. (2024). Synthesis, characterisation, DNA and antibacterial activities of cu (I) complexes of bidentate quinolinyl Schiff base having triphenylphosphine ancillary ligand. Scientia Africana, 23(5), 337-348.

Odulaja, O. S., Amolegbe, S. A. and Olusola, M. A. (2026). Synthesis, structural elucidation, in vitro antibacterial activity of mononuclear Ag (I) complex derived from (E)-N-(4-fluorophenyl)-1-(pyridin-2-yl) methanimine and triphenylphosphine ancillary ligand. Tanzania Journal of Science, 52(2), 1.

Oladipo, S. D., Zamisa, S. J., Badeji, A. A., Ejalonibu, M. A., Adeleke, A. A., Lawal, I. A., . . . Lawal, M. M. (2023). Ni2+ and Cu2+ complexes of N-(2, 6-dichlorophenyl)-N-mesityl formamidine dithiocarbamate structural and functional properties as CYP3A4 potential substrates. Scientific Reports, 13(1), 13414.

Yusuf, T. L., Oladipo, S. D., Zamisa, S., Kumalo, H. M., Lawal, I. A., Lawal, M. M. and Mabuba, N. (2021). Design of new Schiff-Base Copper (II) complexes: Synthesis, crystal structures, DFT study, and binding potency toward cytochrome P450 3A4. ACS omega, 6(21), 13704-13718.

Zoubi, W. A., Al-Hamdani, A. A. S. and Ko, Y. G. (2017). Schiff bases and their complexes: Recent progress in thermal analysis. Separation science and technology, 52(6), 1052-1069.

Published

2026-07-27

How to Cite

Odulaja, O. S., Ayangbesan, C. I., Williams, A. V., Adeleye, C. A., Adeleye, T. F., Olugbile, O. O., Abiola, T. A., Hashimi, A. M., Olusola, M. A., & Bamiro, E. O. (2026). Synthesis, Spectroscopic Studies and Biological Activity of Cu(II) Complex of Schiff Base Ligand 3-((2-(2,4-dinitrophenyl)hydrazineylidene)methyl)pyridine with Triphenylphosphine as Ancillary Ligand. Nigerian Journal of Physics, 35(4), 179-185. https://doi.org/10.62292/njp.v35i4.2026.626

How to Cite

Odulaja, O. S., Ayangbesan, C. I., Williams, A. V., Adeleye, C. A., Adeleye, T. F., Olugbile, O. O., Abiola, T. A., Hashimi, A. M., Olusola, M. A., & Bamiro, E. O. (2026). Synthesis, Spectroscopic Studies and Biological Activity of Cu(II) Complex of Schiff Base Ligand 3-((2-(2,4-dinitrophenyl)hydrazineylidene)methyl)pyridine with Triphenylphosphine as Ancillary Ligand. Nigerian Journal of Physics, 35(4), 179-185. https://doi.org/10.62292/njp.v35i4.2026.626