- Conference date: 24–28 February 2008
- Location: Thiruvananthapuram, Kerala (India)
The complexation ability and the binding mode of the ligand coumarin‐3‐carboxylic acid (HCCA) to La(III), Ce(III), Nd(III), Sm(III), Gd(III) and Dy(III) lanthanide ions (Ln(III)) are elucidated at experimental and theoretical level. The complexes were characterized using elemental analysis, DTA and TGA data as well as NMR and NMR spectra. FTIR and Raman spectroscopic techniques as well as DFT quantum chemical calculations were used for characterization of the binding mode and the structures of lanthanide(III) complexes of HCCA. The metal—ligand binding mode is predicted through molecular modeling and energy estimation of different Ln—CCA structures using B3LYP/6‐31G(d) method combined with a large quasi‐relativistic effective core potential for lanthanide ion. The energies obtained predict bidentate coordination of to Ln(III) ions through the carbonylic oxygen and the carboxylic oxygen. Detailed vibrational analysis of HCCA, and Ln(III) complexes based on both calculated and experimental frequencies confirms the suggested metal—ligand binding mode. The natural bonding analysis predicts strongly ionic character of the Ln(III)‐CCA bonding in complexes studied. With the relatively resistant tumor cell line K‐562 we obtained very interesting in‐vitro results which are in accordance with our previously published data concerning the activity of lanthanide(III) complexes with other coumarin derivatives.
- Nuclear magnetic resonance
- Core binding energies
- Data analysis
Data & Media loading...
Article metrics loading...