Synthesis, Characterization and Breast Anti-cancer Activity of Iron(II), Cobalt(II), Nickel(II) and Copper(II) Complexes with a Hexadentate Schiff Base Ligand Derived from 2,5-Dihydroxy-1,4-benzoquinone with 5-Amino-2-methylphenol

Riyam Baqer Ibrahim(1), Suad Taha Saad(2*)

(1) Department of Chemistry, College of Science for Women, University of Babylon, Hilla 51002, Iraq
(2) Department of Chemistry, College of Science for Women, University of Babylon, Hilla 51002, Iraq
(*) Corresponding Author


The complexes of Fe(II), Co(II), Ni(II), and Cu(II) Schiff base ligand derived from 2,5-dihydroxy-1,4-benzoquinone and 5-amino-2-methylphenol were synthesized. The ligand was synthesized by the reaction between the mentioned ketone and amine in 1:2 molar ratio, respectively. The four metal complexes were synthesized by refluxing the ligand with the related metal(II) chloride salts. The synthesized compounds were characterized using FTIR spectroscopy, UV-visible, 1H-NMR, conductivity, atomic absorption, magnetic susceptibility, and thermogravimetric analysis. According to the results, the chelation between metals and ligand occurs with the imine groups and the deprotonated hydroxyl groups of 2,5-dihydroxy-1,4-benzoquinone and 5-amino-2-methylphenol in the ligand. The conductivity test of the four complexes shows the non-electrolytic nature of them. The magnetic susceptibility values of Fe(II), Co(II), Ni(II), and Cu(II) complexes are 4.20, 4.11, 2.97, and 2.34 B.M, respectively. The thermogravimetric and atomic absorption analyses suggest the general chemical formula for the complexes is [M2(L)(H2O)6]. In addition, the ligand and one of its metal complexes (Co(II) complex) were examined against breast cancer cells, and they gave the IC50 of 101.24 and 129.2 µg/mL, respectively. This result suggests that Co(II) complex is a better anti-cancer agent in comparison with the ligand.


metal complexes; Schiff base; 2,5-dihydroxy-1,4-benzoquinone; 5-amino-2-methylphenol

Full Text:

Full Text PDF


[1] Catalano, A., Sinicropi, M.S., Iacopetta, D., Ceramella, J., Mariconda, A., Rosano, C., Scali, E., Saturnino, C., and Longo, P., 2021, A review on the advancements in the field of metal complexes with Schiff bases as antiproliferative agents, Appl. Sci., 11 (13), 6027.

[2] Otani, N., Fayeulle, A., Nakane, D., Léonard E., and Akitsu T., 2022, Synthesis, identification and antibacterial activities of amino acid Schiff base Cu(II) complexes with chlorinated aromatic moieties, Appl. Microbiol., 2 (2), 438–448.

[3] Mahmoud, W., Refaat, A.M., and Mohamed, G.G., 2020, Nano Schiff base and its metal complexes: Synthesis, characterization tools, biological applications and molecular docking studies, Egypt. J. Chem., 63 (6), 2157–2176.

[4] Rashad, A.A., Ibrahim, F.M., Ahmed, A., Salman, E.A., and Akram, E., 2020, Synthesis and photophysical study of divalent complexes of chelating Schiff base, Baghdad J. Biochem. Appl. Biol. Sci., 1 (01), 5–17.

[5] Adeleke, A.A., Zamisa, S.J., Islam, M.S., Olofinsan, K., Salau, V.F., Mocktar, C., and Omondi, B., 2021, Quinoline functionalized Schiff base silver(I) complexes: Interactions with biomolecules and in vitro cytotoxicity, antioxidant and antimicrobial activities, Molecules, 26 (5), 1205.

[6] More, M.S., Joshi, P.G., Mishra, Y.K., and Khanna, P.K., 2019, Metal complexes driven from Schiff bases and semicarbazones for biomedical and allied applications: A review, Mater. Today Chem., 14, 100195.

[7] Sumrra, S.H., Anees, M., Asif, A., Zafar, M.N., Mahmood, K., Nazar, M.F., Khalid, M., Nadeem, M.A., and Khan, M.U., 2020, Synthesis, structural, spectral and biological evaluation of metals endowed 1,2,4-triazole, Bull. Chem. Soc. Ethiop., 34 (2), 335–351.

[8] Sunjuk, M., Al-Najjar, L., Shtaiwi, M., El-Eswed, B., Al-Noaimi, M., Al-Essa, L., and Sweidan, K., 2022, Transition metal complexes of Schiff base ligands prepared from reaction of aminobenzothiazole with benzaldehydes, Inorganics, 10 (4), 43.

[9] İdil, Ö., Şahal, H., Canpolat, E., and Özkan, M., 2023, Synthesis, characterization, antimicrobial and time killing activities of new sulfa-derived Schiff bases coordinated with Cu(II), Indones. J. Chem., 23 (3), 831–842.

[10] Abd-Elzaher, M.M., Labib, A.A., Mousa, H.A., Moustafa, S.A., Ali, M.M., and El-Rashedy, A.A., 2016, Synthesis, anti-cancer activity and molecular docking study of Schiff base complexes containing thiazole moiety, Beni-Suef Univ. J. Basic Appl. Sci., 5 (1), 85–96.

[11] Abdelnabi, S., Bkhakh, C.K., and Kadhum, M.Y., 2017, Synthesis, spectroscopic characterization and biological study of some new Schiff bases based on 2-hydroxybenzadehyde, J. Adv. Chem., 13 (2), 5995–6005.

[12] Lupașcu, G., Pahonțu, E., Shova, S., Bărbuceanu, S.F., Badea, M., Paraschivescu, C., Neamțu, J., Dinu, M., Ancuceanu, R.V., Drăgănescu D., and Dinu-Pîrvu, E.C., 2021, Co(II), Cu(II), Mn(II), Ni(II), Pd(II), and Pt(II) complexes of bidentate Schiff base ligand: Synthesis, crystal structure, and acute toxicity evaluation, Appl. Organomet. Chem., 35 (4), e6149.

[13] Raczuk, E., Dmochowska, B., Samaszko-Fiertek, J., and Madaj, J., 2022, Different Schiff bases—structure, importance and classification, Molecules, 27 (3), 787.

[14] Sarker, D., Hossen, F.M., Zahan, M.K., Haque, M.M., Zamir, R., and Asraf, M.A., 2020, Synthesis, characterization, thermal analysis and antibacterial activity of Cu(II) and Ni(II) complexes with thiosemicarbazone derived from thiophene-2-aldehyde, J. Mater. Sci. Res. Rev., 5 (2), 15–25.

[15] Xu, P.Y., Wang, Y.T., Yu, Z.M., Li, Y.H., and Wang, S., 2021, New mononuclear Mn(III) complexes with hydroxyl-substituted hexadentate Schiff base ligands, Magnetochemistry, 7 (1), 12.

[16] Abdalrazaq, E., Jbarah, A.A.Q., Al-Noor, T.H., Shinain, G.T., and Jawad, M.M., 2022, Synthesis, DFT calculations, DNA interaction, and antimicrobial studies of some mixed ligand complexes of oxalic acid and Schiff base trimethoprim with various metal ions, Indones. J. Chem., 22 (5), 1348–1364.

[17] Hayder Muneam, A.M., and Al-Amery, M.H.A., 2019, In vitro antioxidant activity of new Schiff base ligand and its metal ion complexes, J. Pharm. Sci. Res., 11 (5), 2051–2061.

[18] Kudelko, A., Olesiejuk, M., Luczynski, M., Swiatkowski, M., Sieranski, T., and Kruszynski, R., 2020, 1,3,4-Thiadiazole-containing azo dyes: synthesis, spectroscopic properties and molecular structure, Molecules, 25 (12), 2822.

[19] Aldelfy, Z., Al-Shamkani, Z., and Al-assadi, M., 2019, 2-Hydroxybenzylidene-4-(4-substitutedphenyl)-2-amino thiazole and their Pt(II) complexes: Synthesis, characterization and biological study, Egypt. J. Chem., 62 (10) 1851–1867.

[20] Özdemir, Ö., 2020, Bis-azo-linkage Schiff bases—Part(II): Synthesis, characterization, photoluminescence and DPPH radical scavenging properties of their novel luminescent mononuclear Zn(II) complexes, J. Photochem. Photobiol., A, 392, 112356.

[21] Hameed, G.F., Wadday, F.Y., Farhan, M.A., and Hussain, S.A., 2021, Synthesis, spectroscopic characterization and bactericidal valuation of some metal(II) complexes with new tridentate heterocyclic azo ligand type (NNO) donor, Egypt. J. Chem., 64 (3), 1333–1345.

[22] Ali, F.J., AL-Ameri, L.A.M., and Ali, A.M., 2021, Synthesis and identification and biological studies of new azo dyes derived from imidazole and their chelate complexes, Indian J. Forensic Med. Toxicol., 15 (2), 1253–1260.

[23] Ahmed, A.H., and Moustafa, M.G., 2020, Spectroscopic, morphology and electrical conductivity studies on Co(II), Ni(II), Cu(II) and Mn(II)-oxaloyldihydrazone complexes, J. Saudi Chem. Soc., 24 (5), 381–392.

[24] Jailani, A., 2020, Synthesis, Characterisation and biological evaluation of tyramine derived Schiff base ligand and its transition metal(II) complexes, Karbala Int. J. Mod. Sci. 6, 225–234.

[25] Özkınalı, S., Yavuz, S., Tosun, T., Ali Köse, D., Gür, M., and Kocaokutgen, H., 2020, Synthesis, spectroscopic and thermal analysis and investigation of dyeing properties of o-hydroxy Schiff bases and their metal complexes, ChemistrySelect, 5 (40), 12624–12634.

[26] Uddin, M.N., Chowdhury, D.A., Rony, M.M., and Halim, M.E., 2014, Metal complexes of Schiff bases derived from 2-thiophenecarboxaldehyde and mono/diamine as the antibacterial agents, Mod. Chem., 2 (2), 6–14.

[27] Ali, A.A.M., and Alabidi, H.M., 2019, Synthesis and spectroscopic study of some transition metal complexes with 2-(4-iodo phenyl azo)-4,5-diphenyl imidazol, J. Phys.: Conf. Ser., 1294 (5), 052021.

[28] Fekri, R., Salehi, M., Asadi, A., and Kubicki, M., 2019, Synthesis, characterization, anti-cancer and antibacterial evaluation of Schiff base ligands derived from hydrazone and their transition metal complexes, Inorg. Chim. Acta, 484, 245–254.

[29] Deghadi, R.G., Mahmoud, W.H., and Mohamed, G.G., 2020, Metal complexes of tetradentate azo-dye ligand derived from 4,4-oxydianiline: Preparation, structural investigation, biological evaluation and MOE studies, Appl. Organomet. Chem., 34 (10), e5883.


Article Metrics

Abstract views : 457 | views : 179

Copyright (c) 2023 Indonesian Journal of Chemistry

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


Indonesian Journal of Chemistry (ISSN 1411-9420 /e-ISSN 2460-1578) - Chemistry Department, Universitas Gadjah Mada, Indonesia.

Analytics View The Statistics of Indones. J. Chem.