New Lanthanum (III) Complex – Synthesis, Characterization, and Cytotoxic Activity

Abstract

The complex of lanthanum (III) was synthesized reacting the respective inorganic salt with 5-aminoorotic acid in amounts equal to the metal:ligand molar ratio of 1:3. The complex was prepared by adding an aqueous solution of lanthanum (III) nitrate to an aqueous solution of the ligand, subsequently raising the pH of the mixture gradually to approx. 5.0 through addition of a dilute solution of sodium hydroxide. The structure of the final complex was determined by means of spectral data (IR, Raman,( 1)H-NMR) and elemental analysis. Significant differences in the IR spectrum of the complex were observed as compared to the spectrum of the ligand. A comparative analysis of the Raman spectrum of the complex with that of the free 5-aminoorotic acid allowed a straightforward assignment of the vibrations of the ligand groups involved in coordination. The ligand and the complex were tested for the cytotoxic activities on the chronic myeloid leukemia derived K-562, overexpressing the BCR-ABL fusion protein and the non-Hodgkin lymphoma derived DOHH-2, characterized by a re-expression of the anti-apoptotic protein bcl-2 cell lines. The results obtained indicate that the tested compounds exerted a considerable cytotoxic activity upon the evaluated cell lines in a concentration-dependent matter, which enabled the construction of dose-response curves and the calculation of the corresponding IC(50 )values. The inorganic salt exerted a very weak cytotoxic effect on these cells, which is in contrast to the lanthanum (III) complex.

Understanding the Self-Assembling Behavior of Biological Building Block Molecules: A Spectroscopic and Microscopic Approach

“…After 48 h of 2 mM Eu 3+ addition, the DCM lifetime distribution shifts to 1003–2069 ps with a maximum at ∼1690 ps. This type of inhibition is postulated by the complex formation between Eu 3+ and orotic acid through COO – as reported earlier, − and the morphological changes due to lanthanide complex formation also bring new insight into the field of supramolecular chemistry. Again, Banerjee et al have completely blocked the COO – group of orotic acid by esterification, i.e., the synthesis of methyl orotate.…”

Coumarins: Old Compounds with Novel Promising Therapeutic Perspectives

“…In the last years the potential application of coumarins with metal complexes as cyto-selective therapeutic agents for cancer therapy gained growing interest. Complexes of coumarins with lanthanum(III), zirconium(IV) or cerium(III) represent interesting metalorganic compounds with antitumor activity in different cell lines [19,[87][88][89][90]. The cytotoxicity of the lanthanum complex of bis-coumarins in the chronic myeloid leukemia cell line is partly mediated by the stimulation of programmed cell death whereas the inorganic salt exerts a very weak cytotoxic effect [90].…”

Lanthanide(III) complexes are more active inhibitors of the Fenton reaction than pure ligands

“…Given that the ligands used are well-known biologically active compounds, we compared them with the lanthanide(III) complexes which we have characterized. [22][23][24][25][26]28,29 Detailed analysis of AOA and Ln(III)-AOA systems revealed that the binding mode in the complexes was bidentate through the carboxylic oxygen atoms. It has been suggested that CCA binds to Ln(III) ions through both oxygen atoms of the carboxylic and carbonylic groups.…”

“…The synthesis of the lanthanide(III) complexes of AOA and CCA as well as their theoretical, analytical, spectral, and structural characterization have been previously reported by us. [22][23][24][25][26]28,29 Shortly: the compounds used for preparing the solutions were Merck products, p.a. grade:…”

“…21 In a series of papers, we investigated the molecular structure, energetic, and spectroscopic properties of different coumarin derivatives and their lanthanide complexes, as well as their pharmacological activity. [15][16][17][22][23][24][25][26] These studies highlighted the potential for developing novel lanthanide complexes mainly as anti-cancer therapeutics. However, more analogs are required to obtain better activity profiles for this class of compounds.…”