Ability of two novel α-amino acid-based tridentate ligands to complex Fe3+ in solution
Two novel α-amino acid-based tridentate ligands, L1 and L2, were synthesized, and characterized by use of spectroscopic methods. Potentiometric and spectrophotometric methods were used to study the pH-dependent protonation behavior of the ligands and their complexation towards Fe(III) in aqueous medium of ionic strength, µ = 0.1 M KCl at 25 ± 1 °C. The stability constants of complex species of the types FeLH3, FeLH2, FeLH, FeL, and FeL2 (L = L1 or L2) were determined, and probable structures of the ferric complexes were proposed on the basis of molecular modeling. The complexing ability of the ligands was compared with that of deferiprone (a drug used for medical treatment of iron intoxication) and transferrin (the main Fe-binding protein in plasma).
KeywordsTridentate ligands Amino acids Potentiometry Spectrophotometry Protonation and stability constants
The authors would like to thank the Council of Scientific and Industrial Research (CSIR), Human Resource Development Group, PUSA, New Delhi, India, for financial Support and the National Institute of Technology, Kurukshetra, India, for providing infrastructure and research facilities.
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