Research of new mixed-chelate copper complexes with Quinoxaline N1,N4-dioxide derivatives and Alanine as ligands, potential antimycobacterial agents

Abstract

Three new mixed-chelate copper complexes with 3-aminoquinoxaline-2-carbonitrile N1,N4-dioxide derivatives and alanine as ligands were synthesized in solid state. The spectroscopic characterization (FTIR, EPR, UV-Vis) showed that copper coordinated through the amine and the N-oxide groups of the quinoxaline derivatives and the amine and carboxylate moieties from alanine forming a dimeric species. The tree complexes showed in vitro activity against M. tuberculosis H37Rv (ATCC 27294) similar to that of ethambutol while they are inactive against E. coli and S. aureus.Tres nuevos complejos mixtos de cobre con derivados de 3-aminoquinoxalina-2-carbonitrilo N1,N4-dióxido y alanina como ligandos fueron sintetizados en estado sólido. La caracterización espectroscópica (FTIR, EPR, UV-Vis) mostró que el Cu coordina con el grupo amino y el N-óxido del derivado quinoxalínico y con el amino y el carboxilato de la alanina formando especies diméricas. Los tres complejos mostraron actividad frente al M. tuberculosis H37Rv (ATCC 27294) similar a la del etambutol, mientras que fueron inactivos frente a E. coli y S. aureus.PEDECIB