Theoretical study of dipeptide complexes of copper(II)

The l,l-Phe-Leu-Cu(II), l,l-Leu-Phe-Cu(II), l,l-Phe-Met-Cu(II), and l,l-Met-Phe-Cu(II) systems were studied using molecular modelling. The results obtained, which are in good agreement with results obtained by potentiometric studies show a significant increase in stability of copper complexes, when an aromatic residue is located in C-terminal (compared to the l,l-dipeptides containing the same amino acid residues), this phenomenon is attributed to the interaction between the d-orbital of copper and the π-electrons of the aromatic ring.