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Updated: Apr 9, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Copper(ii) complexes of macrocyclic and open-chain pseudopeptidic ligands: synthesis, characterization and
Enrico Faggi1, Raquel Gavara, Michael Bolte
1Departamento de Química Biológica y Modelización Molecular, IQAC-CSIC, Jordi Girona, 16-26, E-08034 Barcelona, Spain. enrico.faggi@iqac.csic.es ignacio.alfonso@iqac.csic.es.
Abstract:
Mono- and dinuclear Cu(ii) complexes were prepared with pseudopeptidic open chain and macrocyclic ligands, respectively. They were characterized by UV-vis spectroscopy, EPR, HRMS and X-ray diffraction. The Cu(ii) cation is coordinated by two amines and two deprotonated amides, in a slightly distorted square planar coordination geometry. The complexes interact with several substituted dicarboxylates, as shown by UV-vis titrations and EPR experiments. The interaction of both mono- and dinuclear complexes with very similar dicarboxylates of biological interest (malate and aspartate) resulted in strikingly different outcomes: in the first case a ternary complex [ligand...metal...dicarboxylate] was obtained almost quantitatively, while in the latter, the Cu(ii) displacement to form Cu(Asp)2 was predominant.
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