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Synthesis, spectral, thermal, antibacterial and molecular docking studies of some metal(II) complexes of 2-(1,3-benzothiazol-2-ylamino)naphthalene-1,4-dione


The ketoamine, 2-(1,3-benzothiazol-2-ylamino)naphthalene-1,4-dione(HL) and its Mn(II), Co(II), Ni(II), Cu(II), Pd(II) and Zn(II) complexes were synthesized and characterized by NMR, FTIR, and electronic spectroscopies with elemental, thermal, room temperature magnetic susceptibility, and molar conductivity measurements. The elemental, spectral, and thermal analysis corroborated the proposed molecular formulae for the complexes as [ML(OAc)]aH2O {M = Co, Ni, Cu, Zn} and [ML2]bH2O {M = Mn}. In addition, magnetic moments and electronic spectra data indicated a tetrahedral/square-planar geometry for all the metal complexes, while molar conductance measurements in DMSO established the covalent nature of the metal complexes. The in vitro antibacterial studies of the ketoamine and its metal complexes against K. oxytoca, P. aeruginosa, E. coli, B. cereus, and S. aureus showed that the compounds exhibited broad-spectrum antibacterial activities against the bacteria strains, with an inhibitory zone of 8.0–25.0 mm. Furthermore, molecular docking studies were conducted in order to examine the molecular interactions of the complexes with different enzymes of bacterial strains. The complexes showed good molecular interactions with all the receptors; phosphopentomutase, dioldehydratase, Ftsz, penicillin-binding protein 5, and peptidyl-tRNA hydrolase except for the bulky palladium complex. The results obtained from the molecular docking studies supported and provided a possible mechanistic basis for the experimentally observed antibacterial efficacies.

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  1. 1.

    N. Raman, A. Sakthivel, K. Rajasekaran, Synthesis and spectral characterization of antifungal sensitive schiff base transition metal complexes. Mycobiology 35, 150–153 (2007)

    CAS  Article  Google Scholar 

  2. 2.

    A.A. Al-Amiery, Inhibition effects of a synthesized novel 4-aminoantipyrine derivative on the corrosion of mild steel in hydrochloric acid solution together with quantum chemical studies. Med. Chem. Res. 21, 3204–3213 (2012)

    CAS  Article  Google Scholar 

  3. 3.

    D.S. Musmade, M.R. Sherkar, N.S. Pendbhaje, Synthesis and evaluation of some novel [3-isonicotinoyl-5-(4-substituted)-2,3-dihydro-1,3,4-oxadiazol-2-yl] derivatives for anti-inflammatory activity. Pharmacologyonline 1, 993–1000 (2011)

    Google Scholar 

  4. 4.

    A. Ignatious, J. Rahul, P. Pushpa, R.T. Pardasani, Recent advances in 1,4 benzoquinone chemistry. J. Braz. Chem. Soc. 22, 385–421 (2011)

    Article  Google Scholar 

  5. 5.

    S. Patai, Z. Rappaport, The Chemistry of Quinonoid Compounds, vol. II (Wiley, New York, 1988)

    Google Scholar 

  6. 6.

    R.H. Thomson, Naturally Occurring Quinones IV. Recent Advances (Blackie, London, 1997)

    Google Scholar 

  7. 7.

    S. Spyros, Hydroxyquinones: synthesis and reactivity. Molecules 5, 1291–1330 (2000)

    Article  Google Scholar 

  8. 8.

    J. Yin, L.S. Liebeskind, Chemistry of trisquinones. J. Org. Chem. 63, 5726–5727 (1998)

    CAS  Article  Google Scholar 

  9. 9.

    I.L. Lluvia, D.N.F. Sendar, Y.S.B. Sonia, S.G. Aide, Naphthoquinones: biological properties and synthesis of lawsone and derivatives—a structured review. Rev. Fac. Quím. Farm. 21 (2014)

  10. 10.

    A.R. Mehendale, R.H. Thomson, Binaphthoquinones in lomatia ferruginea. Phytochemistry 14, 801–802 (1975)

    CAS  Article  Google Scholar 

  11. 11.

    U. Sharma, D. Katoch, S. Sood, N. Kumar, B. Singh, A. Thakur, Synthesis, antibacterial and antifungal activity of 2-amino-1,4-naphthoquinone using silica-supported perchloric acid (HClO4–SiO2) as a mild recyclable and highly efficient heterogeneous catalyst Gulati. Indian J. Chem. 52B, 1431–1440 (2013)

    CAS  Google Scholar 

  12. 12.

    W. Nittayananta, K. Pangsomboon, P. Panichayupakaranant, N. Chanowanna, S. Chelae, V. Vuddhakul, P. Sukhumungoon, N. Pruphetkaew, Effects of lawsone methyl ether mouthwash on oral Candida in HIV-infected subjects and subjects with denture stomatisis. J. Oral Pathol. Med. 42, 698–704 (2013)

    CAS  Article  Google Scholar 

  13. 13.

    A. Mahapatra, T. Tshikalange, Synthesis and HIV-1 reverse transcriptase inhibition activity of 1,4-naphthoquinone derivatives. Chem. Nat. Compd. 47, 883–887 (2012)

    CAS  Article  Google Scholar 

  14. 14.

    G.J. Kapadia, G.S. Rao, R. Sridhar, E. Ichiishi, M. Takasaki, N. Suzuki, T. Konoshima, A. Iida, H. Tokuda, Chemoprevention of skin cancer: effect of Lawsonia inermis L. (Henna) leaf powder and its pigment artifact, lawsone in the Epstein–Barr virus early antigen activation assay and in two-stage mouse skin carcinogenesis models. Med. Chem. 13, 1500–1507 (2013)

    CAS  Google Scholar 

  15. 15.

    S. Jiménez-Alonso, H.C. Orellana, A. Estévez-Braun, A.G. Ravelo, E. Pérez-Sacau, F. Machín, Design and synthesis of a novel series of pyranonaphthoquinones as topoisomerase II catalytic inhibitors. J. Med. Chem. 51, 6761–6772 (2008)

    Article  Google Scholar 

  16. 16.

    D. Bhasin, S.N. Chettiar, J.P. Etter, M. Mok, P.K. Li, Anticancer activity and SAR studies of substituted 1,4-naphthoquinones. Bioorg. Med. Chem. 21, 4662–4669 (2013)

    CAS  Article  Google Scholar 

  17. 17.

    F. Nourollah, V.P. Rahul, P.G. Shridhar, B.S. Fareed, G. Rajesh, Y.R. Sandhya, Crystal structure, NMR and theoretical investigations on 2-(o-hydroxy-anilino)-1,4-napthoquinone. J. Mol. Struct. 966, 144–151 (2010)

    Article  Google Scholar 

  18. 18.

    O. Pawar, A. Patekar, A. Khan, L. Kathawate, S. Haram, G. Markad, V. Puranik, S. Salunke-Gawali, J. Mol. Struct. 1059, 68–74 (2014)

    CAS  Article  Google Scholar 

  19. 19.

    S. Pal, M. Jadhav, T. Weyhermüller, Y. Patil, M. Nethaji, U. Kasabe, L. Kathawate, K.V. Badireenath, S. Salunke-Gawali, J. Mol. Struct. 1049, 355–361 (2013)

    CAS  Article  Google Scholar 

  20. 20.

    K. Laxmi, V.J. Pranya, K.D. Tapan, P. Sanjima, N. Milind, W. Thomas, G.P. Vedavati, V.K. Badireenath, S. Sunita, Reaction between lawsone and aminophenol derivatives: synthesis, characterization, molecular structures and antiproliferative activity. J. Mol. Struct. 1075, 397–405 (2014)

    Article  Google Scholar 

  21. 21.

    C. Bates, C. Pasternak, The incorporation of labeled amino sugars by Bacillus subtilis. Biochem. J. 96, 147–154 (1965)

    CAS  Article  Google Scholar 

  22. 22.

    H. Chmara, R. Andruszkiewicz, E. Borowski, Inactivation of glucosamine-6-phosphate synthetase from Salmonella typhimurium LT2 by fumaroyl diaminopropanoic acid derivatives, a novel group of glutamine analogs. BBA Protein Struct. Mol. Enzymol. 870, 357–366 (1986)

    CAS  Article  Google Scholar 

  23. 23.

    G. Jose, T.S. Kumara, G. Nagendrappa, H. Sowmya, J.P. Jasinski, S.P. Millikan, N. Chandrika, S.S. More, B. Harish, New polyfunctional imidazo[4,5-C]pyridine motifs: synthesis, crystal studies, docking studies and antimicrobial evaluation. Eur. J. Med. Chem. 77, 288–297 (2014)

    CAS  Article  Google Scholar 

  24. 24.

    P. Shyma, B. Kalluraya, S. Peethambar, S. Telkar, T. Arulmoli, Synthesis, characterization and molecular docking studies of some new 1,3,4-oxadiazolines bearing 6-methylpyridine moiety for antimicrobial property. Eur. J. Med. Chem. 68, 394–404 (2013)

    CAS  Article  Google Scholar 

  25. 25.

    A.A. Osowole, R. Kempe, R. Schobert, Synthesis, spectral, thermal, in vitro antibacterial and anticancer activities of some metal(II) complexes of 3-(-1-(4-methoxy-6-methyl)-2- pyrimidinylimino) methyl-2-napthol. Int. Res. J. Pure Appl. Chem. 2, 105–129 (2012)

    CAS  Article  Google Scholar 

  26. 26.

    A.A. Osowole, I. Ott, O.M. Ogunlana, Synthesis, spectroscopic, anticancer and antimicrobial properties of some metal(II) complexes of 2-[(2,3-dihydro-1H-inden-4-ylimino) methyl]-5-nitrophenol. Int. J. Inorg. Chem. 2012, 6 (2012)

    Google Scholar 

  27. 27.

    A.A. Osowole, A.C. Ekennia, B.O. Achugbu, Synthesis, spectroscopic characterization and antibacterial properties of some metal(II) complexes of 2-(6-methoxybenzothiazol-2-ylimino)methyl)-4-nitrophenol. Res. Rev. J. Pharm. Anal. 2, 1–5 (2013)

    Google Scholar 

  28. 28.

    A.A. Osowole, A.C. Ekennia, Synthesis, spectroscopic characterization and in vitro antibacterial properties of some metal(II) complexes of 4-nitro-6-[(4-thiophen-3-ylphenylimino)-methyl]-phenol. Cent. Point J. 19, 1–10 (2013)

    Google Scholar 

  29. 29.

    G.A. Kolawole, A.A. Osowole, Synthesis and characterization of some metal(II) complexes of isomeric unsymmetrical Schiff-bases and their adducts with triphenyl phosphine. J. Coord. Chem. 62, 1437–1440 (2009)

    CAS  Article  Google Scholar 

  30. 30.

    A.C. Ekennia, D.C. Onwudiwe, A.A. Osowole, Synthesis, spectral, thermal stability and antibacterial studies of copper, nickel and cobalt complexes of N-methyl-N-phenyldithiocarbamate. J. Sulfur Chem. 36, 96–104 (2015)

    CAS  Article  Google Scholar 

  31. 31.

    A.C. Ekennia, D.C. Onwudiwe, C. Ume, E.E. Ebenso, Mixed ligand complexes of N-methyl-N-phenyl dithiocarbamate: synthesis, characterisation, antifungal activity, and solvent extraction studies of the ligand. Bioinorg. Chem. Appl. 2015, 10 (2015)

    Google Scholar 

  32. 32.

    D.C. Onwudiwe, Y.B. Nthwane, A.C. Ekennia, E. Hosten, Synthesis, characterization and antimicrobial properties of some mixed ligand complexes of Zn(II) dithiocarbamate with different N-donor ligands. Inorg. Chim. Acta 447, 134–141 (2016)

    CAS  Article  Google Scholar 

  33. 33.

    W. Humphrey, A. Dalke, K. Schulten, VMD—visual molecular dynamics. J. Mol. Graph. 14, 33–38 (1996)

    CAS  Article  Google Scholar 

  34. 34.

    D. Santos-Martins, S. Forli, M.J. Ramos, A.J. Olson, AutoDock4(Zn): an improved AutoDock force field for small-molecule docking to zinc metalloproteins. J. Chem. Inf. Model. 54, 2371–2379 (2014)

    CAS  Article  Google Scholar 

  35. 35.

    O. Trott, A.J. Olson, AutoDock Vina: improving the speed and accuracy of docking with a new scoring function, efficient optimization and multithreading. J. Comput. Chem. 31, 455–461 (2010)

    CAS  Google Scholar 

  36. 36.

    S.R. Cherayath, J. Alice, C.P. Prabhakaran, Palladium(II) complexes of Schiff bases derived from 5-amino-2,4-(1H,3H) pyrimidinedione (5-aminouracil) and 1,2-dihydro-1,5-dimethyl-2-phenyl-4-amino-3H-pyrazol-3-one. Trans. Met. Chem. 15, 449–453 (1990)

    CAS  Article  Google Scholar 

  37. 37.

    P.A. Ajibade, O.G. Idemudia, Synthesis, characterization and antibacterial studies of Pd(II) and Pt(II) complexes of some diaminopyrimidine derivatives. Bioinorg. Chem. Appl. 2013, 1–8 (2013)

    Article  Google Scholar 

  38. 38.

    T.L. Yang, W.W. Qin, Transition metal manganese(II), nickel(II), copper(II) and zinc(II)complexes of a new Schiff base ligand: synthesis, characterization and antitumor activity studies. Pol. J. Chem. 80, 1657–1662 (2006)

    CAS  Google Scholar 

  39. 39.

    M.G. AbdEl-Wahed, M.S. Refat, M.S. El-Meghharbel, Metal complexes of antiuralethic drug: synthesis, spectroscopic characterization and thermal study on allopurinol complexes. J. Mol. Struct. 888, 416–429 (2008)

    CAS  Article  Google Scholar 

  40. 40.

    A.B.P. Lever, Inorganic Electronic Spectroscopy (Elsevier Publishers, Amsterdam, 1973)

    Google Scholar 

  41. 41.

    N. Raman, S. Ravichandran, C. Thangaraja, Copper(II), cobalt(II), nickel(II) and zinc(II) complexes of Schiff base derived from benzil-2,4-dinitrophenylhydrazone with aniline. J. Chem. Sci. 116, 215–219 (2004)

    CAS  Article  Google Scholar 

  42. 42.

    M. Soenmez, M.A. Sekerci, New heterocyclic Schiff base and its metal complexes. Synth. React. Inorg., Met.-Org., Nano-Met. Chem. 34, 489–502 (2004)

    CAS  Article  Google Scholar 

  43. 43.

    M. Soenmez, A. Levent, M. Sekerci, Synthesis, characterization, and thermal investigation of some metal complexes containing polydentate ONOdonor heterocyclic Schiff base ligand. Russ. J. Coord. Chem. 30, 655–659 (2004)

    CAS  Article  Google Scholar 

  44. 44.

    D.C. Onwudiwe, P.A. Ajibade, Thermal Studies of Zn(II), Cd(II) and Hg(II) complexes of some N-alkyl-N-phenyl-dithiocarbamates. Int. J. Mol. Sci. 13, 9502–9513 (2012)

    CAS  Article  Google Scholar 

  45. 45.

    A.A. Osowole, R. Kempe, R. Schobert, K. Effenberger, Synthesis, spectroscopic, thermal, and in vitro anticancer properties of some M(II) complexes of 3-(-1-(4,6-dimethyl-2-pyrimidinylimino)methyl-2-naphthol. Synth. React. Inorg., Met.-Org., Nano-Met. Chem. 41, 825–833 (2011)

    CAS  Article  Google Scholar 

  46. 46.

    A.A. Osowole, S.A. Balogun, Spectral, magnetic, thermal and antibacterial properties of some metal(II) complexes of aminoindanyl schiff base. Eur. J. Appl. Sci. 4, 06–13 (2012)

    CAS  Google Scholar 

  47. 47.

    P.L. Franceschini, M. Morstein, H. Berke, H.W. Schmalle, Volatile beta-ketoiminato- and beta-diketiminato-based zirconium complexes as potential MOCVD precursors. Inorg. Chem. 42, 7273–7282 (2003)

    CAS  Article  Google Scholar 

  48. 48.

    M.N. Patel, H.N. Joshi, C.R. Patel, Copper(II) complexes with norfloxacin and neutral terpyridines: cytotoxic, antibacterial, superoxide dismutase and DNA-interaction approach. Polyhedron 40, 159 (2012)

    CAS  Article  Google Scholar 

  49. 49.

    A.A. Abdel-Aziz, H.A. Elbadawy, Spectral, electrochemical, thermal, DNA binding ability, antioxidant and antibacterial studies of novel Ru(III) Schiff base complexes. Spectrochim. Acta 124, 404 (2014)

    CAS  Article  Google Scholar 

  50. 50.

    L. Malhota, S. Kumar, K.S. Dhindsa, Synthesis, characterization and microbial activity of Co(II), Ni(II), Cu(II) and Zn(II) complexes of aryloxyacetic acid and hydrazides. Indian J. Chem. 32A, 457–459 (1993)

    Google Scholar 

  51. 51.

    D.P. Timothy, P.N. David, R.W. Guy, V.P. Vanessa, E.W. Brian, O.B. Brian, M.I. Tina, Bacillus cereus phosphopentomutase is an alkaline phosphatase family member that exhibits an altered entry point into the catalytic cycle. J. Biol. Chem. 286, 8043–8054 (2011)

    Article  Google Scholar 

  52. 52.

    N. Shibata, K. Mori, N. Hieda, Y. Higuchi, M. Yamanishi, T. Toraya, Release of a damaged cofactor from a coenzyme B12-dependent enzyme: X-ray structures of diol dehydratase-reactivating factor. Structure 13, 1745 (2005)

    CAS  Article  Google Scholar 

  53. 53.

    C.M. Tan, A.G. Therien, J. Lu, S.H. Lee, A. Caron, C.J. Gill, C. Lebeau-Jacob, L. Benton-Perdomo, J.M. Monteiro, P.M. Pereira, N.L. Elsen, J. Wu, K. Deschamps, M. Petcu, S. Wong, E. Daigneault, S. Kramer, L. Liang, E. Maxwell, D. Claveau, J. Vaillancourt, K. Skorey, J. Tam, H. Wang, T.C. Meredith, S. Sillaots, L. Wang-Jarantow, Y. Ramtohul, E. Langlois, F. Landry, J.C. Reid, G. Parthasarathy, S. Sharma, A. Baryshnikova, K.J. Lumb, M.G. Pinho, S.M. Soisson, T. Roemer, Restoring methicillin-resistant Staphylococcus aureus susceptibility to β-lactam antibiotics. Sci. Transl. Med. 4, 635 (2012)

    Google Scholar 

  54. 54.

    G. Nicola, J. Tomberg, R.F. Pratt, R.A. Nicholas, C. Davie, Crystal structure of Escherichia coli penicillin-binding protein 5 bound to a tripeptide boronic acid inhibitor: a role for Ser-110 in deacylation. Biochemistry 49, 8094 (2010)

    CAS  Article  Google Scholar 

  55. 55.

    A. Singh, A. Kumar, L. Gautam, P. Sharma, M. Sinha, A. Bhushan, P. Kaur, S. Sharma, A. Arora, T.P. Singh, Structural and binding studies of peptidyl-tRNA hydrolase from Pseudomonas aeruginosa provide a platform for the structure based inhibitor design against peptidyl-tRNA hydrolase. Biochem. J. 463, 329 (2014)

    CAS  Article  Google Scholar 

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ACE thanks the University of Ibadan, Ibadan and Federal University, Ndufu-Alike, Ikwo, for the provision of research facilities and research leave, respectively. Dr. Damian C. Onwudiwe, North West University, South Africa is thanked for his assistance during characterization of synthesized compounds.

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Correspondence to Anthony C. Ekennia.

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Osowole, A.A., Ekennia, A.C., Olubiyi, O.O. et al. Synthesis, spectral, thermal, antibacterial and molecular docking studies of some metal(II) complexes of 2-(1,3-benzothiazol-2-ylamino)naphthalene-1,4-dione. Res Chem Intermed 43, 2565–2585 (2017).

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  • Antibacterial
  • Molecular docking
  • Ketoamine
  • Thermogravimetric