Copper(II) complexes with 2-pyridyl-quinazoline ligands with potential activity for Chagas disease treatment

Chagas disease is classified as a neglected tropical disease, caused by the parasite Trypanosoma cruzi, it still lacks effective treatment. In this context, the present study aimed to synthesize and characterize a series of 2-pyridyl-quinazoline ligands with chlorine, fluorine, methyl, and hydrogen substituents and the respective copper(II) mononuclear coordination compounds. The complexes contains a 2-pyridyl-quinazoline ligand unit coordinated to copper(II) through a chelate ring and two chloride ions. The compounds showed trypanocidal activity against the trypomastigote form consistent with literature data for organic compounds and copper(II) complexes – the quinazolyl derivatives exhibited half-maximal inhibitory concentration (IC₅₀) values between 2.43 and 0.23 μmol L^-1 and the complexes between 0.43 and 0.14 μmol L^-1. For the amastigote morphology, only the series of complexes was evaluated, with fluorine showing the most promising result, with an IC₅₀ of 0.32 μmol L^-1. Cytotoxicity tests showed that the complexes are less selective than the ligands.