Synthesis, Spectroscopic, Biological and DFT Studies of 2,4,6-Tris(4-Carboxyphenylimino-41-Formylphenoxy)-1,3,5-Triazine and its Trinuclear Dy(III) and Er(III) Salen Capped Complexes


  • Uchechukwu Susan Oruma University of Nigeria, Nsukka, 410001, Nigeria.
  • Pius Oziri Ukoha University of Nigeria, Nsukka, 410001, Nigeria.
  • Collins U. Ibeji University of Nigeria, Nsukka, 410001, Nigeria.
  • Lawrence Nnamdi Obasi University of Nigeria, Nsukka, 410001, Nigeria.
  • Obinna C. Okpareke University of Nigeria, Nsukka, 410001, Nigeria


Tripodal Schiff base; 1,3,5-triazine, trinuclearDy/Er(III) complexes; antimicrobial activity, antimalarial activity; DFT, , docking


Communication in Physical Sciences 2020, 7(3): 182-202

Authors: Uchechukwu S. Oruma, Pius O. Ukoha, Collins U. Ibeji, Lawrence N. Obasi, Obinna C. Okpareke, Ebubechukwu N. Dim, Klaus Jurkschat and Ponnadurai Ramasami

Received 29 August  2021/Accepted 23 September 2021

A tripodal Schiff base ligand, 2,4,6-tris(4-carboxyphenylimino-41-formylphenoxy)-1,3,5-triazine (H3CT) and its trinuclear Dy(III) and Er(III) complexes were synthesized. Characterization of these compounds was done via UV-Visible, IR, 1H, and 13C NMR spectroscopies, elemental analysis, and molar conductivity measurements. The spectral studies indicate that the ligand is hexadentate and coordinates to Dy/Er(III) ions through the oxygen atoms of the carboxylic group. The trinuclear complexes were characterized as being bridged by a carboxylic group to the Dy(III) and Er(III) salen centers and display a coordination number of six. Biological studies revealed that the Dy(III) complex showed the highest activity against tested microorganisms and also gave the highest percentage parasitemia inhibition (84.0 %) relative to Artesunate (87.2 %). DFT calculations were carried out to enhance understanding of H3CT at the molecular level based on  (B3LYP)/6-31+G(d,p). The molecular docking results revealed the binding mode of H3CT complexed with Staphylococcus aureus.


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Author Biographies

Uchechukwu Susan Oruma, University of Nigeria, Nsukka, 410001, Nigeria.

Coordination Chemistry and Inorganic Pharmaceuticals Unit,

Department of Pure and Industrial Chemistry

Pius Oziri Ukoha, University of Nigeria, Nsukka, 410001, Nigeria.

Coordination Chemistry and Inorganic Pharmaceuticals Unit, Department of Pure and Industrial Chemistry

Collins U. Ibeji, University of Nigeria, Nsukka, 410001, Nigeria.

Department of Pure and Industrial Chemistry

Lawrence Nnamdi Obasi, University of Nigeria, Nsukka, 410001, Nigeria.

Department of Pure and Industrial Chemistry

Obinna C. Okpareke, University of Nigeria, Nsukka, 410001, Nigeria

Department of Pure and Industrial Chemistry


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