Organometallic Schiff bases derived from 5-nitrothiophene and 5-nitrofurane: Synthesis, crystallographic, electrochemical, ESR and antiTrypanosoma cruzi studies

•Cyrhetrenyl and ferrocenyl N-imine derivates from 5-nitrothiophene have been designed and prepared.•The antichagasic activity was tested against epimastigotes and tripamostigotes form of Trypanosoma cruzi.•Cyrhetrenyl derivatives shower lower reduction potential and better antitrypanosomal activity than their ferrocenyl analogues.

In the search for new therapeutic tools for the treatment of American trypanosomiasis, a series of novel ferrocene and cyrhetrene imine compounds, derived from 5-nitro-heterocycles, were designed, synthesized and characterized. The 1H and 13C NMR spectra indicated that these compounds adopted an anti-(E) conformation in solution, and this was confirmed by X-ray crystallography for one of the complexes (NT2). To study the relationship between the physical–chemical properties of N-iminyl substituents of nitrofurfuryl and nitrothienyl groups and their antitrypanosomal activity, we have carried out cyclic voltammetry and electron spin resonance studies of a series of organometallic imine compounds. The results demonstrated that the electronic properties of the side chain of the 5-nitroheterocyclic compound could be correlated to its trypanocidal effect.

Graphical abstractOrganometallic compounds containing 5-nitroheterocyclic-imine (furane and thiopene) have been synthesized and characterized by spectroscopy and X-ray crystallography. The antichagasic activity have been tested against the epimastigotes and tripamostigotes strains of Trypanosoma cruzi. Tryponocidal effects were correlated to electronic nature of organometallic fragments by cyclic voltammetry and electron spin resonance studies.Figure optionsDownload full-size imageDownload as PowerPoint slide