Antibacterial and Anticancer Studies of Mononuclear and Binuclear Complexes of Tellurium(IV), Tantalum(V), Selenium(IV), and Niobium(V) Urate by Spectroscopic Methods

• Published in: Journal of applied spectroscopy 2021-05, Vol.88 (2), p.323-331
• Main Authors: Al-Saif, F. A., Al-Humaidi, J. Y., Binjawhar, D. N., Bakhsh, H. A., Refat, M. S.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Anticancer properties; Atomic/Molecular Structure and Spectra; Cancer; Carbonyls; Coordination compounds; Imidazole; Klebsiella; Ligands; Metal chlorides; Niobium; Nitrogen; NMR; Nuclear magnetic resonance; Physics; Physics and Astronomy; Selenium; Tantalum; Tellurium; Uric acid
• ISSN: 0021-9037; 1573-8647
• DOI: 10.1007/s10812-021-01177-5

Novel tellurium(IV), tantalum(V), selenium(IV), and niobium(V) urate complexes were prepared with molar ratios 1:1 and 2:1 (metal:ligand). The uric acid (H 4 UA) ligand was reacted with TeCl 4 , TaCl 5 , SeCl 4 , and NbCl 5 metal chlorides in the presence of NaOH to yield mononuclear and binuclear complexes. The mononuclear tellurium (IV) and tantalum(V) complexes formulas [Te(H 3 UA)(H 2 O) 3 (Cl)]∙2Cl·2H 2 O ( I ) and [Ta(H 3 UA)(H 2 O) 2 (Cl) 2 ]·2Cl∙4H 2 O ( II ), as well as binuclear selenium(IV) and niobium(V) complexes [Se 2 (H 2 UA)(Cl) 4 ]·2Cl∙4H 2 O ( III ) and [Nb 2 (H 2 UA) (Cl)8] ∙3H 2 O ( IV ), were obtained in the presence of NaOH at pH 8–9. The metal complexes were characterized by elemental analyses, FTIR, 1 H-NMR, electronic, conductivity, and thermal analyses. In the case of mononuclear complexes, the coordinating sites are the pyrimidine carbonyl oxygen atom of C(6)=O group and imidazole nitrogen of deprotonated N(7)–H. In addition to these coordinating sites, the pyrimidine carbonyl oxygen atom of C(2)=O and pyrimidine nitrogen of deprotonated N(3)–H are involved in coordination in binuclear complexes. The metal urate complexes exhibited six-coordinate geometries, while the binuclear selenium is four-coordinate. The antibacterial and anticancer activities of the urate complexes were investigated. No antibacterial activity was observed in any treatments, except for gram-negative Klebsiella, which showed a slight effect. The metal complexes showed high proportions of cell viability percentage after treatment in both colorectal adenocarcinoma (Caco-2) and breast cancer (MCF-7) cell lines using the neutral red uptake assay.