Stereospecific ligands and their complexes IX: Synthesis, characterization and antimicrobial activity of ethyl esters of (S,S)-ethylenediamine-N,N′-di-2-propanoic and (S,S)-ethylenediamine-N,N′-di-2-(3-methyl)-butanoic acids and corresponding platinum(IV)

The synthesis of ethyl esters of (S,S)-ethylenediamine-N,N′-di-2-propanoic and (S,S)-ethylenediamine-N,N′-di-2-(3-methyl)-butanoic acids and corresponding platinum(IV) complexes are reported. The complexes have been prepared by direct reaction of K2[PtCl6] and ethyl esters of the acids mentioned above. The esters and complexes were characterized by elemental microanalysis, infrared, 1H and 13C NMR spectroscopy. The spectroscopically predicted structures of the synthesized complexes were confirmed by X-ray analysis of the [PtCl4(det-(S,S)-eddp)]. Antimicrobial activity of ligands and corresponding platinum(IV) complexes was investigated against 29 species of microorganisms. Testing was performed by microdilution method and minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) have been determined. Tested ligands and corresponding platinum(IV) complexes demonstrated the significant activity against some G+ bacteria. On the other hand, these complexes demonstrated moderate and low antibacterial and antifungal activity.

Graphical abstractThe complex has been obtained by direct reaction of corresponding potassium hexahalogenidoplatinate(IV) with neutralized O,O′-diethyl-(S,S)-ethylenediamine-N,N′-di-2-propanoate dihydrochloride (det-S,S-eddp·2HCl). The crystal structure of the complex unit is given below.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The synthesis of two bidentate ligands and corresponding platinum(IV) complexes. ► The compounds were characterized by infrared, NMR spectroscopy and X-ray analysis. ► Antimicrobial activity was investigated against 29 species of microorganisms.