Trinuclear Ni(II), Pd(II) and Cu(II) complexes containing the 2-hydroxy-benzaldehyde-ferrocenyl-sulfonylhydrazone ligand: Synthesis, structural characterization and antiplasmodial evaluation

Abstract

The novel 2-hydroxy-benzaldehyde-ferrocenyl-sulfonylhydrazone ligand [(η5-C5H5)Fe(η5-C5H4SO2NH-NCH-C6H4-2-OH)] (HL) and its nickel(II), palladium(II) and copper(II) complexes (1a–c) have been synthesized. All compounds were characterized using conventional spectroscopic and analytical techniques (infrared, 1H and 13C NMR, mass spectrometry and elemental analysis). The proposed molecular structures of HL, 1a and 1c were confirmed by single-crystal X-ray crystallography. The in vitro antiplasmodial activity of the new ligand and its corresponding metal complexes was evaluated against the chloroquine-sensitive (NF54) strain of the human malaria parasite, Plasmodium falciparum, and showed only modest activities in the micromolar range.