Synthesis, characterization and antimicrobial evaluation of mono- and polynuclear ferrocenyl-derived amino and imino complexes

A series of ferrocenyl mono- and polynuclear complexes conjugated to imino and amino scaffolds was prepared. The imino complexes were prepared via a Schiff base condensation reaction between (E)-4-vinylferrocenylbenzaldehyde and various amines. The amino complexes were prepared by reductive amination reactions using the same precursors. The compounds were characterized using standard spectroscopic and analytical techniques including Nuclear Magnetic Resonance (NMR) spectroscopy, Infrared (IR) spectroscopy and mass spectrometry. The compounds were screened against Mycobacterium tuberculosis as well as the NF54 chloroquine-sensitive (CQS) strain of Plasmodium falciparum. Overall, the complexes showed moderate in vitro biological activity, with the ferrocenylimines exhibiting enhanced activity against M. tuberculosis compared to the corresponding amines. The ferrocenylimines also displayed moderate activity against P. falciparum, with the second-generation polyimine complex exhibiting the highest activity in vitro. The ferrocenylamines exhibit promising antiplasmodial activity, enhanced compared to the imines, with the silicon-containing derivative and the second-generation dendrimer showing good activity.