Stereospecific ligands and their complexes. XI: Synthesis, characterization and antimicrobial activity of palladium(II) complexes with some alkyl esters of (S,S)-ethylenediamine-N,N′-di-2-(3-methyl)-butanoic acid

Abstract

Three new ligand precursors and their palladium(II) complexes of general formula [PdCl{(S,S)-(R)eddv}] (R = n-propyl, n-butyl and n-pentyl; S,S-eddv = (S,S)-ethylenediamine-N,N′-di-2-(3-methyl)-butanoate) have been synthesized and characterized by microanalysis, infrared, 1H and 13C NMR spectroscopy and mass spectrometry. In vitro antimicrobial activity for these ligands and complexes is investigated. Testing is performed by microdilution method and minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) have been determined. Testing is conducted against 15 microorganisms (five strains of pathogenic bacteria, three species of probiotic bacteria, two yeast species and five pathogenic fungi). Tested ligands, with a few exceptions, show very low antimicrobial activity. Palladium(II) complexes show selective and moderate activity. The difference in antimicrobial activity between ligands and corresponding palladium(II) complexes is noticed and it is always higher with palladium(II) complexes. © 2012 Elsevier B.V. All rights reserved.