Palladium(II)/N,N-disubstituted-N′-acylthioureas complexes as anti-Mycobacterium tuberculosis and anti-Trypanosoma cruzi agents

The new complexes of Pd(II) with N,N-disubstituted-N′-acylthioureas:[(1) [Pd(dppf)(N,N-dimethyl-N′-benzoylthioureato-k2O,S)]PF6, (2) [Pd(dppf)(N,N-diethyl-N′-benzoylthioureato-k2O,S)]PF6, (3) [Pd(dppf)(N,N-dibuthyl-N′-benzoylthioureato-k2O,S)]PF6, (4) [Pd(dppf)(N,N-diphenyl-N′-benzoylthioureato-k2O,S)]PF6, (5) [Pd(dppf)(N,N-diethyl-N′-furoylthioureato-k2O,S)]PF6, (6) [Pd(dppf)(N,N-diphenyl-N′-furoylthioureato-k2O,S)]PF6, (7) [Pd(dppf)(N,N-dimethyl-N′- thiophenylthioureato-k2O,S)]PF6, and (8) [Pd(dppf)(N,N-diphenyl-N′-thiophenylthioureato-k2O,S)]PF6, were prepared and characterized by elemental analysis, and spectroscopic techniques. The structures of complexes (2), (3), (5), (6) and (8) had their structures determined by X-ray crystallography, confirming the coordination of the ligands with the metal through sulfur and oxygen atoms, forming distorted square-planar geometries. These complexes have shown antibacterial activity against anti-Mycobacterium tuberculosis H37Rv ATCC 27294. The complexes exhibited antiparasitic activity against Trypanosoma cruzi, while the metal-free thioureas did not. The results demonstrated that the compounds described here can be considered as promising anti-Mycobacterium tuberculosis and anti-T. cruzi agents, since in both cases their in vitro activity were better than reference drugs available for the treatment of both diseases.