Synthesis, characterization and antimicrobial activity of palladium(II) complexes with O,O'-dialkyl esters of (S,S)-ethylenediamine-N,N'-di-(3,3′-1H-indol-3yl)-propionic acid

Abstract

© 2020 Elsevier B.V. A series of four new ligands of general formula R2-S,S-eddtrp·2HCl (L1–L4) and their palladium(II) complexes of general formula [PdCl2(R2-S,S-eddtrp)] (C1–C4) where R = ethyl, 1-propyl, 1-butyl and 1-pentyl; S,S-eddtrp·2HCl = ethylenediamine-N,N′-di-(3,3′-1H-indol-3yl)propionic acid dihydrochloride have been synthesized and characterized by elemental microanalysis, infrared, 1H and 13C NMR spectroscopy. The proposed structures of all compounds were examined by density functional theory (DFT). The ligands (L1–L4) and Pd(II) complexes (C1–C4) were screened for their antimicrobial activity against 19 microorganisms and minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) were determinated. All tested ligands and complexes exhibited the highest antimicrobial activity on Escherichia coli ATCC 25922, being in range or higher than positive control, tetracycline.