Theoretical Study of Tripeptides Complexes of Copper(II)

Abstract

The L,L-Phe-Gly-Phe-Cu(II), L,L-Phe-Phe-Gly-Cu(II), L,L-Phe-Gly-Phe-Cu(II) systems were studied using molecular modelling. The results obtained, are in good agreement with results obtained by potentiometric studies show a significant increase in stability of copper complexes, when one aromatic or two aromatic residues is located in C-terminal side (compared to the L,L-tripeptides containing the same amino acid residues). This phenomenon is attributed to the interaction between the d-orbital of copper(II) and the π-electrons of the aromatic ring and is observed in dipeptides and recently in tripeptides systems.