Investigation of Some Novel Schiff Base Copper(II) Complexes of 2-aminophenol and ortho Substituted Benzaldehydes as Potential Antiseptic Agents


  • Felicia Ndidi Ejiah University of Lagos, Lagos, Nigeria
  • Tolulope Mojisola Fasina University of Lagos, Lagos, Nigeria
  • Neerish Revaprasadu University of Zululand, Private Bag X1001, KwaDlangezwa, South Africa
  • Folasade Tolulope Ogunsola University of Lagos, Lagos, Nigeria
  • Oluwole Babafemi Familoni University of Lagos, Lagos, Nigeria


2-aminophenol, antibacterial, copper complexes, Schiff bases


Communication in Physical Sciences, 2024, 11(2): 276-287

Authors: Felicia Ndidi Ejiah, Tolulope Mojisola Fasina, Neerish Revaprasadu, Folasade Tolulope Ogunsola and Oluwole Babafemi Familoni

Received: 18 January 2024/Accepted: 02 May 2024

The increasing microbial resistance to existing antiseptics and disinfectants has necessitated the search for new compounds with potential effects against pathogenic organisms. Schiff bases and their metal complexes are important class of compounds for the search of new antibacterial agents.  In line with this, novel copper (II) complexes with Schiff bases derived from ortho substituted benzaldehydes and 2-aminophenol have been synthesized. The compounds were fully characterized using elemental analysis, atomic absorption spectroscopy, infrared spectroscopy, 1H NMR, electronic absorption spectroscopy, magnetic susceptibility measurements and thermal gravimetry analysis. The Schiff bases and their metal complexes were screened for in-vitro antibacterial activities against 6 human pathogenic bacteria; Escheriachia coli (ATCC 8739), Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 19582), Bacillus cereus (10702), Enterococcus faecalis (ATCC 29212) and Kribsella pneumonia (ATCC 10031). Ampicillin was used as a reference compound. The result showed that methoxy and chloro substituted Schiff base metal complexes exhibited higher antibacterial activity compared to ampicillin. Our results show that these complexes can be employed as active ingredients in development of broad-spectrum antiseptics agents. Further research on mechanism and cytotoxicity would provide understanding of key biological entities to identify drug targets.


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Author Biographies

Felicia Ndidi Ejiah, University of Lagos, Lagos, Nigeria

1Department of Chemistry

Tolulope Mojisola Fasina, University of Lagos, Lagos, Nigeria

Department of Chemistry

Neerish Revaprasadu , University of Zululand, Private Bag X1001, KwaDlangezwa, South Africa

Department of Chemistry

Folasade Tolulope Ogunsola, University of Lagos, Lagos, Nigeria

Department of Medical Microbiology, College of Medicine

Oluwole Babafemi Familoni, University of Lagos, Lagos, Nigeria

Department of Chemistry


Abd El-Wahab, Z. H. (2007). Mononuclear metal complexes of organic carboxylic acid derivatives: Synthesis, spectroscopic characterization, thermal investigation and antimicrobial activity. Spectrochimica Acta Part A, 67,pp. 25-38.

Aligiannis, N., Kalpoutzakis, E., Mitaku, S., & Chinou, I. B. (2001). Composition and antimicrobial activity of the essential oils of two origanum species. Journal of Agric and Food Chemistry, 49, pp. 4168-4170.

Al-Sha’alan, N. H. (2007). Antimicrobial activity and spectral, magnetic and thermal studies of some transition metal complexes of a Schiff base hydrazone containing a quinoline moiety. Molecules, 12, pp. 1080-1091.

Bauer, A. W., Kirby, W. N. N., Sherris, J. C., & Turck, M. (1996). Antibiotic susceptibility testing by a standardized single disk method. American Journal of Clinical Pathology, 45, pp. 493-496.

Beshir, A. B., Guchhait, S. K., Gascon, J. A., & Fenteany, G. (2008). Synthesis and structure-activity relationships of metal-ligand complexes that potentently inhibit cell migration. Bioorganic and Medicinal Chemistry Letters, 18, pp. 498-504.

Boulechfar, C., Ferkous, H., Delimi, A., Djedouani, A., Kahlouche, A., Boublia, A., Darwish, A. S., Lemaoui, T., Verma, R., & Benguerba, Y. (2023). Schiff bases and their metal complexes: a review on the history, synthesis, and applications. Inorganic Chemistry Communications, 150, 110451.

Eloff, J. N. (1998). A sensitive and quick microplate method to determine the minimal inhibitory concentration of plants extracts for bacteria. Planta Medica, 64, pp. 711-714.

Fang, W. Y., Ravindar, L., Rakesh, K. P., Manukumar, H. M., Shantharam, C. S., Alharbi, N. S., & Qin, H. L. (2019). Synthetic approaches and pharmaceutical applications of chloro-containing molecules for drug discovery: A critical review. European Journal of Medicinal Chemistry, 173, pp. 117-153.

George, R. S., Joseph, R., & George, K. E. (1993). Study of poly-Schiff's bases as a protective agent in natural rubber. International Journal Polymer Materials, 23, pp. 17-26.

Howsaui, H.B., Sharfalddin, A.A., Abdellattif, M.H., Basaleh, A.S., & Hussien, M.A. (2021). Synthesis, Spectroscopic Characterization and Biological Studies of Mn(II), Cu(II), Ni(II), Co(II) and Zn(II) Complexes with New Schiff Base of 2-((Pyrazine-2-ylimino)methyl)phenol. Appl. Sci., 11(19), 9067.

Issa, R. M., Khedr, A. M., & Rizk, H. F. (2005). UV–vis, IR and 1H NMR spectroscopic studies of some Schiff bases derivatives of 4-aminoantipyrine. Spectrochimica Acta Part A, 62, pp. 621–629.

Jouad, E. M., Riou, A., Allain, M., Khan, M. A., & Bouet, G. M. (2001). Synthesis, structural and spectral studies of 5-methyl 2-furaldehyde thiosemicarbazone and its Co, Ni, Cu and Cd complexes. Polyhedron, 20, pp. 67-74.

Karabocek, N., Karabocek, S., & Kormali, F. (2007). Mono-, di-, and trinuclear copper(II) complexes of a Schiff base ligand, 2{(E)-[(6-{[(1E)-(2-hydroxyphenyl) methylene]amino}pyridine-2-yl)imino]-methyl}phenol. Turkish Journal of Chemistry, 31, pp. 271-277.

Khan, S. A., Siddiqui, A. A., & Bhatt, S. (2002). Analgesic activity of isatin derivatives. Asian Journal of Chemistry, 14, pp. 1117-1118.

Lakshmi, B., Avaji, P. G., Shivananda, K. N., Nagella, P., Manohar, S. H., & Mahendra, K. N. (2011). Synthesis, spectral characterization and in-vitro microbiological evaluation of novel glyoxal, biacetyl and benzil bis-hydrazone macrocyclic Schiff bases and their Co(II), Ni(II) and Cu(II) complexes. Polyhedron, 30, pp. 1507–1515.

Liew, S.K., Malagobadan, S., Arshad, N.M., & Nagoor, N.H. (2020). A Review of the Structure–Activity Relationship of Natural and Synthetic Antimetastatic Compounds. Biomolecules, 10, 1, 138.

Mohamed, G. G. (2006). Synthesis, characterization and biological activity of bis(phenylimine) Schiff base ligands and their metal complexes. Spectrochimica Acta Part A, 64, pp. 188-195.

Mohamed, G. G., Omar, M. M., & Hindy, A. M. (2005). Synthesis, characterization and biological activity of some transition metals with Schiff base derived from 2-thiophene carboxaldehyde and aminobenzoic acid. Spectrochimica Acta Part A, 62, pp. 1140-1150.

Mohamed, N. I., & Salah, E. A. S. (2007). Synthesis, characterization and use of Schiff bases as fluorimetric analytical reagents. E-Journal of Chemistry, 4, pp. 531-535.

Mounika, K., Anupama, B., Pragathi, J., & Gyanakumari, C. (2010). Synthesis, characterization and biological activity of a Schiff base derived from 3-ethoxy salicyaldehyde and 2-aminobenzoic acid and its transition metal complexes. Journal of Scientific Research, 2, pp. 513-524.

Nishat, N., Khan, S. A., Parveen, S., & Rasool, R. (2010). Antimicrobial agents: synthesis, spectral, thermal and biological aspects of a polymeric Schiff base and its polymer metal(II) complexes. Journal of Coordination Chemistry, 63, pp. 3944-3955.

Patil, S. A., Unk, S. N., Kulkarni, A. D., Naik, V. H., Kamble, U., & Badami, P. S. (2011). Spectroscopic, in-vitro antibacterial and antifungal studies of Co(II), Ni(II) and Cu(II) complexes with 4-chloro-3-coumarinaldehyde Schiff bases. Journal of Coordination Chemistry, 64, pp. 323-336.

Sari, N., Arslan, S., Logoglu, E., & Sakiyan, I. (2003). Antibacterial activities of some new amino acid-Schiff bases. Gazi University Journal of Science, 16, pp. 283-288.

Singh, A. K., & Quraishi, M. A. (2012). Study of some bidentate Schiff bases of isatin as corrosion inhibitors for mild steel in hydrochloric acid solution. International Journal of Electrochemical Science, 7, pp. 3222-3241.

Sivakumar, K. K., & Rajasekaran, A. (2013). Synthesis, in-vitro antimicrobial and antitubercular screening of Schiff bases of 3-amino-1-phenyl-4-[2-(4-phenyl-1,3-thiazol-2-yl)hydrazin-1-ylidene]-4,5-dihydro-1H-pyrazol-5-one. Journal of Pharmacy and BioAllied Sciences, 5, pp. 126-135.

Tikhomirov, E. (1987). WHO programme for the control of hospital infections. Chemotherapy, 6, pp. 148-151.

Valentovic, M. A., Ball, J. G., Hong, S. A., Rogers, B., Meadows, H., Harmon, R. C., & Rankin, G. O. (1996). In-vitro toxicity of 2- and 4-Chloroaniline: Comparisons with 4-amino-3-chlorophenols, 2-amino-5-chlorophenol and aminophenol. Toxicology, 10, pp. 713-720.

Wang, Y-E., Yang, D., Huo, J., Chen, L., Kang, Z., Mao, J., & Zhang, J. (2021). Design, Synthesis, and Herbicidal Activity of Thioether Containing 1,2,4-Triazole Schiff Bases as Transketolase Inhibitors. Journal of Agricultural and Food Chemistry, 69, pp. 11773-11780.

Xiao, Z., Xue, J., Tan, S., Li, H., & Zhu, H. (2007). Synthesis, structure, and structure–activity relationship analysis of enamines as potential antibacterial. Bioorganic and Medicinal Chemistry, 15, pp. 4212-4219.

Zhang, L. X., Liu, U., Cia, L. H., Hu, Y. J., Yin, J., & Hu, P. Z. (2006). Inhibitory study of some novel Schiff base derivatives on Staphylococcus aureus by microcalorimetry. Thermochimica Acta, 440, pp. 51-56.