Ni(II) and Cu(II) complexes of pyridine-carboxamide Schiff base: Synthesis, characterization, and antioxidant activities evaluation

Abstract

This research introduces two novel Schiff base complexes: [LNi(H2O)2]H2O and [LCu]3H2O, where L represents (E)-2-(5-bromo-2-hidroksibenzilidenamino)-6-metil-4,5,6,7-tetrahidrotiyeno[2,3-c]piridin-3-karboksamid. These complexes were synthesized by reacting of Schiff base ligand (L) containing ON donor atoms with an equimolar amount of NiCl2∙6H2O and Cu(NO3)2∙3H2O salts. The compounds were extensively characterized using various analytical and spectroscopic techniques, including elemental analysis, FT-IR, 1H-NMR, 13C-NMR, UV-Vis spectroscopy, mass spectrometry, magnetic susceptibility measurements, molar conductivity, and thermogravimetric analysis. Additionally, the antioxidant properties of both the ligand and complexes were evaluated in vitro using three methods: DPPH free radical scavenging activity, ABTS+ cation radical scavenging activity, and CUPRAC reducing power. From the analytical data, it was observed that the Ni(II) complex has an octahedral structure and the Cu(II) complex has a square planar structure. The antioxidant activity results indicated that some of the complex compounds demonstrated superior antioxidant effects compared to the Schiff base ligand.

Keywords

• Schiff base
• metal complexes
• spectroscopic method
• DPPH
• ABTS
• CUPRAC

References

1. A. El-Lateef, M. Hany, M.A. Elbastawesy, T.M. Abdelghani Ibrahim, M.M. Khalaf, M. Gouda, M.M. Morcoss, Design, synthesis, docking study, and antiproliferative evaluation of novel Schiff base-benzimidazole hybrids with VEGFR-2 inhibitory activity, Molecules, 28 (2023) 481.
2. W. Derafa, N.A.A. Elkanzi, A.M. Ali and A. Abdou, Three Co(II), Ni(II) and Cu(II) Schiff base complexes incorporating 2-[(4-{[(4-methylphenyl)sulfonothioyl]oxy}phenyl)methylene]amino}benzoic acid: Synthesis, structural, DFT, biological and molecular docking investigation, Bull. Chem. Soc. Ethiop., 38 (2024) 325-346.
3. G.K. Obiyenwa, A.C. Tella, S.O. Okwoli, O.S. Oluwafemi, Solid state synthesis, spectroscopic, X-ray and antibacterial studies of Zn(II) and Fe(III) complexes of pyridine-3-carboxamide and 2-hydroxybenzoic acid, Chem. Afr., 7 (2024) 2017-2027.
4. L.H. Abdel-Rahman, A.A. Abdelghani, A.A. AlObaid, D.A. El-ezz, I. Warad, M. R. Shehata, E.M. Abdalla, Novel bromo and methoxy substituted Schiff base complexes of Mn(II), Fe(III), and Cr(III) for anticancer, antimicrobial, docking, and ADMET studies, Sci. Rep., 13 (2023) 3199.
5. B. Kumar, J. Devi, A. Manuja, Synthesis, structure elucidation, antioxidant, antimicrobial, anti-inflammatory and molecular docking studies of transition metal (II) complexes derived from heterocyclic Schiff base ligands, Res. Chem. Intermed., 49 (2023) 2455-2493.
6. B. Ma, W. Tan, J. Zhang, Y. Mi, Q. Miao, Z. Guo, Preparation and characterization of chitosan derivatives bearing imidazole ring with antioxidant, antibacterial, and antifungal activities, Starch‐Stärke, 75 (2023) 2200204.
7. I. Waziri, M.T. Kelani, M.O. Oyedeji-Amusa, A.K. Oyebamiji, L-C.C. Coetzee, A.S. Adeyinka, A.J. Muller, Synthesis and computational investigation of N,N-dimethyl-4-[(Z)-(phenylimino)methyl]aniline derivatives: Biological and quantitative structural activity relationship studies, J. Mol. Struct., 1276 (2023) 134756.
8. N. Turan, A. Savci, K. Buldurun, Y. Alan, R. Adigüzel, Synthesis and chemical structure elucidation of two Schiff base ligands, their iron(II) and zinc(II) complexes, and antiradical, antimicrobial, antioxidant properties, Lett. Org. Chem., 13 (2016) 343-351.

9. P. Sılku, S. Özkınalı, Z. Öztürk, A. Asan, D.A. Köse, Synthesis of novel Schiff bases containing acryloyl moiety and the investigation of spectroscopic and electrochemical properties, J. Mol. Struct., 1116 (2016) 72-83.
10. S. Özkınalı, Ş. Yavuz, T. Tosun, D.A. Köse, M. Gür, H. Kocaokutgen, Synthesis, spectroscopic and thermal analysis and investigation of dyeing properties of o‐hydroxy Schiff bases and their metal complexes, ChemistrySelect, 5 (2020) 12624-12634.
11. K. Alomar, A. Landreau, M. Kempf, M.A. Khan, M. Allain, G. Bouet, Synthesis, crystal structure, characterization of zinc(II), cadmium(II) complexes with 3-thiophene aldehyde thiosemicarbazone (3TTSCH). Biological activities of 3TTSCH and its complexes, J. Inorg. Biochem., 104 (2010) 397-404.
12. L. Zarei, Z. Asadi, M. Dusek, V. Eigner, Homodinuclear Ni(II) and Cu(II) Schiff base complexes derived from o-vanillin with a pyrazole bridge: Preparation, crystal structures, DNA and protein (BSA) binding, DNA cleavage, molecular docking and cytotoxicity study, J. Photochem. Photobiol. A: Chem., 374 (2019) 145-160.
13. I.S. Meeran, T.W. Raja, V.N.A. Dusthakeer, M.M.N. Ali, S.S. Tajudeen, T.K. Shabeer, An insight into antimycobacterial and antioxidant potentials of INH-Schiff base complexes and in silico targeting of MtKasB receptor of M. tuberculosis, New J. Chem., 46 (2022) 4620-4633.
14. H. Hrichi, N.A.A. Elkanzi, A.M. Ali, A. Abdou, A novel colorimetric chemosensor based on 2‑[(carbamothioylhydrazono)methyl]phenyl 4‑methylbenzenesulfonate (CHMPMBS) for the detection of Cu(II) in aqueous medium, Res. Chem. Intermed., 49 (2023) 2257-2276.
15. Y.T. Chen, S.N. Zhang, Z.F. Wang, Q.M. Wei, S.H. Zhang, Discovery of thirteen cobalt(II) and copper(II) salicylaldehyde Schiff base complexes that induce apoptosis and autophagy in human lung adenocarcinoma A549/DDP cells and that can overcome cisplatin resistance in vitro and in vivo, Dalton Trans., 51 (2022) 4068-4078.
16. S. Karthik, P. Priya, T. Gomathi, Synthesis, characterization, antimicrobial, anti-diabetic, anti-inflammatory and anti-cancer studies of Schiff base metal(II) complexes derived from mixed Schiff base ligands, Ind. J. Chem., 63 (2024) 112-120.
17. M.E. Alkış, K. Buldurun, Y. Alan, N. Turan, A. Altun, Electroporation enhances the anticancer effects of novel Cu(II) and Fe(II) complexes against human glioblastoma cells, Chem. Biodiversity, 20 (2023) e202200710.
18. A. Savcı, K. Buldurun, M.E. Alkış, Y. Alan, N. Turan, Synthesis, characterization, antioxidant and anticancer activities of a new Schiff base and its M(II) complexes derived from 5‑fluorouracil, Med. Oncol., 39 (2022) 172.
19. M.S. Hossain, P.K. Roy, C.M. Zakaria, M. Kudrat-E-Zahan, Selected Schiff base coordination complexes and their microbial application: A review, Int. J. Chem. Stud., 6 (2018) 19-31.
20. F.S. Al-Fartusie, S.N. Mohssan, Essential trace elements and their vital roles in human body, Indian J. Adv. Chem. Sci., 5 (2017) 127-136.
21. A.Y. Hassan, H.A. Mohamed, Synthesis and biological evaluation of thieno[2,3-c]pyridines and related heterocyclic systems, Asian J. Chem., 21 (2009) 3947-3961.
22. M. Khera, N. Goel, Noncovalent interactions, structure elucidation and docking studies of anti-fungal pyridine carboxamide derivatives of Co(II), Ni(II), Cu(II) & Zn(II), Polycycl. Aromat. Compd., 44 (2023) 4416-4429.
23. F.E. Öztürkkan Özbek, M. Sertçelik, M. Yüksek, A. Elmalı, E. Şahin, The superiority of the classical synthesis compared to the hydrothermal synthesis upon the structural, optical absorption and fluorescent properties of new Cd(II) 3-fluorobenzoate complexes with pyridine3-carboxamide/pyridine-3-carboxylate, Inorg. Chim. Acta, 509 (2020) 119694.
24. M. Bingöl, N. Turan, Schiff base and metal (II) complexes containing thiophene-3-carboxylate: Synthesis, characterization and antioxidant activities, J. Mol. Struct., 1205 (2020) 127542.
25. N. Turan, K. Buldurun, F. Türkan, A. Aras, N. Çolak, M. Manikanta, E. Bursal, A. Mantarcı, Some metal chelates with Schiff base ligand: synthesis, structure elucidation, thermal behavior, XRD evaluation, antioxidant activity, enzyme inhibition, and molecular docking studies, Mol. Divers., 26 (2022) 2459-2472.
26. O. Aydın, Synthesis, spectral characterization and antioxidant activity studies of new pyridine-carboxamide Schiff base and its Ni(II), Cu(II) and Cd(II) complexes. Master Thesis, Natural and Applied Science, Muş Alparslan University, Muş, Turkey, 2022.
27. E. Bursal, A. Aras, Ö. Kılıç, Evaluation of antioxidant capacity of endemic plant Marrubium astracanicum subsp. macrodon: Identification of its phenolic contents by using HPLC-MS/MS, Nat. Prod. Res., 33 (2019) 1975-1979.
28. R. Apak, K. Güçlü, B. Demirata, M. Özyürek, S.E. Çelik, B. Bektaşoğlu, K.I. Berker, D. Özyurt, Comparative evaluation of various total antioxidant capacity assays applied to phenolic compounds with the CUPRAC assay, Molecules, 12 (2007) 1496-1547.
29. E. Bursal, A. Aras, Ö. Kılıç, P. Taslimi, A.C. Gören, İ. Gülçin, Phytochemical content, antioxidant activity, and enzyme inhibition effect of Salvia eriophora Boiss. & Kotschy against acetylcholinesterase, α‐amylase, butyrylcholinesterase, and α‐glycosidase enzymes, J. Food Biochem., 43 (2019) e12776.
30. A. Reiss, N. Cioateră, A. Dobritescu, M. Rotaru, A.C. Carabet, F. Parisi, A. Gănescu, I. Dăbuleanu, I.C. Spînu and P. Rotaru, Bioactive Co(II), Ni(II), and Cu(II) complexes containing a tridentate sulfathiazole-based (ONN) Schiff base, Molecules, 26 (2021) 3062.
31. H.F. Abd El-Halim, M.M. Omar, G.G. Mohamed, M.A. El-Ela Sayed, Spectroscopic and biological activity studies on tridentate Schiff base ligands and their transition metal complexes, Eur. J. Chem., 2 (2011) 178-188.
32. V.K. Bhovi, K. Bharathi, S.P. Melinmath, V. Basavanna, S. Ningaiah, Transition metal(II) complexes of (E)-N-(4-methylbenzylidene)-2-((Z)-(4-methylbenzylidene)amino)benzamides: Synthesis, characterization and their biological evaluation, Biointerface Res. Appl. Chem., 12 (2022) 3607-3617.
33. Z. Beigi, A.H. Kianfar, H. Farrokhpour, M. Roushani, M.H. Azarian, W.A.K. Mahmood, Synthesis, characterization and spectroscopic studies of nickel(II) complexes with some tridentate ONN donor Schiff bases and their electrocatalytic application for oxidation of methanol, J. Mol. Liq., 249 (2018) 117-125.
34. E. Pahontu, V. Fala, A. Gulea, D. Poirier, V. Tapcov, T. Rosu, Synthesis and characterization of some new Cu(II), Ni(II) and Zn(II) complexes with salicylidene thiosemicarbazones: Antibacterial, antifungal and in vitro antileukemia activity, Molecules, 18 (2013) 8812-8836.
35. Y.B. Zemede, D. Nithyakalyani, S.A. Kumar, Synthesis, characterization and antimicrobial properties of some transition metal complexes with NS-chelating Schiff base ligand incorporating thiophene and sulfonamide moieties, Asian J. Chem., 27 (2015) 941-948.
36. A.M. Hassan, A.O. Said, B.H., Heakal, A. Younis, W.M. Aboulthana, M.F. Mady, Green synthesis, characterization, antimicrobial and anticancer screening of new metal complexes incorporating Schiff base, ACS Omega, 7 (2022) 32418-32431.
37. H.M.A. El-Lateef, A.M. Ali, M.M. Khalaf, A. Abdou, New Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) mixed-ligand complexes: structural, DFT, biological, and molecular docking studies, Bull. Chem. Soc. Ethiop., 38 (2024) 397-416.
38. H.A.M. Bennour, F.M. Elmagbari, A.N. Hammouda, R.M. EL-Ferjani, Y.O.B. Amera, S.M. Soliman, G.E. Jackson, Synthesis, characterization and density functional theory (DPT) studies of a triazine ring with a mixed ligand Schiff base complexes, Results Chem., 5 (2023) 100775.
39. C.G.L. Nongpiur, M.M. Ghate, D.K. Tripathi, K.M. Poluri, W. Kaminsky, M.R. Kollipara, Study of versatile coordination modes, antibacterial and radical scavenging activities of arene ruthenium, rhodium and iridium complexes containing fluorenone based thiosemicarbazones, J. Org. Chem., 957 (2022) 122148.
40. L.E.T. Ngoudjou, A.G. Paboudam, A.P. Yepseu, M. Kuate, G. Doungmo, P.T. Ndifon, Synthesis, characterization, and biological activity of Cu(II), Ni(II), and Zn(II) complexes of a tridentate heterocyclic Schiff base ligand derived from thiosemicarbazide and 2-benzoylpyridine, Eur. J. Chem., 13 (2022) 299-306.
41. S. Gurusamy, M. Sankarganeshb, N. Revathic, R.N. Ashad, A. Mathavan, Synthesis and structural investigation of o-vanillin scaffold Schiff base metal complexes: Biomolecular interaction and molecular docking studies, J. Mol. Liq., 369 (2023) 120941.
42. N. Turan, E. Tanış, K. Buldurun, N. Çolak, Synthesis, structure, DFT calculations, and in silico toxic potential of Ni(II), Zn(II), and Fe(II) complexes with a tridentate Schiff base, Russ. J. Gen. Chem., 91 (2021) 1572.
43. K. Buldurun, N. Turan, E. Bursal, A. Aras, A. Mantarcı, N. Çolak, F. Türkan and İ. Gülçin, Synthesis, characterization, powder X-ray diffraction analysis, thermal stability, antioxidant properties and enzyme inhibitions of M(II)-Schiff base ligand complexes, J. Biomol. Struct. Dyn., 39 (2021) 6480-6487.
44. K. Buldurun, N. Turan, A. Savcı, Y. Alan, N. Çolak, Synthesis, characterization, X-ray diffraction analysis of a tridentate Schiff base ligand and its complexes with Co(II), Fe(II), Pd(II) and Ru(II): Bioactivity studies, Iran. J. Chem. Chem. Eng., 41 (2022) 2635-2649.
45. M. Pichandi, S. Shanmugam, Synthesis, characterization of Schiff base metal complexes with 1,3 propanediamine as secondary chelates and their DNA binding, DNA cleavage, cytotoxicity, antioxidant and activities, J. Mol. Struct., 1307 (2024) 137932.
46. M. Pichandi, S. Shanmugam, M. Alka, S. Jyoti, Synthesis, spectral, antioxidant, in vitro cytotoxicity activity and thermal analysis of Schiff base metal complexes with 2,2′-bipyridine-4,4′-dicarboxylic acid as co-ligand, J. Mol. Struct., 1268 (2022) 133669.
47. B. Vivekanand, K.M. Raj, B.H.M. Mruthyunjayaswamy, Synthesis, characterization, antimicrobial, DNA-cleavage and antioxidant activities of 3-((5-chloro-2-phenyl1H-indol-3-ylimino)methyl)quinoline-2(1H)-thione and its metal complexes, J. Mol. Struct., 1079 (2015) 214-224.
48. A. Savcı, K. Buldurun, G. Kırkpantur, A new Schiff base containing 5-FU and its metal complexes: Synthesis, characterization, and biological activities, Inorg. Chem. Commun., 134 (2021) 109060.