The synthesis and antiparasitic activity of aryl- and ferrocenyl-derived thiosemicarbazone ruthenium(ii)–arene complexes

Abstract

A series of aryl-functionalized and ferrocenyl monothiosemicarbazone compounds (L1-L4) were synthesized in moderate yields via a general Schiff-base condensation reaction. The thiosemicarbazone (TSC) ligands were reacted with the ruthenium dimer [Ru(Ar)(μ-Cl)Cl](2) (Ar = benzene; p-cymene) to yield a series of cationic mononuclear ruthenium(II)-arene thiosemicarbazone complexes of the general type [Ru(Cl)(TSC)(Ar)]Cl (1-8). The thiosemicarbazone ligands act as bidentate chelating ligands that coordinate to the ruthenium(ii) ion via the imine nitrogen and the thione sulfur atoms. The thiosemicarbazone ligands, as well as their metal complexes, were characterized by NMR, IR spectroscopy and ESI(+)-mass spectrometry. The molecular structure of the mononuclear ruthenium(II)-arene thiosemicarbazone complex (6) was determined by single-crystal X-ray diffraction analysis. The ruthenium(II)-arene thiosemicarbazone complexes were further evaluated for their in vitro antiparasitic activities against the Plasmodium falciparum chloroquine-sensitive (NF54) and chloroquine-resistant (Dd2) strains, as well as the G3 strain of Trichomonas vaginalis.

Synthesis and molecular studies of half-sandwich arene ruthenium and Cp*Rh/Cp*Ir complexes containing (3-picolyl)thiourea derivatives as N,S-bidentate donor ligands

“…Furthermore the distances between metal and centroid of arene/Cp* ring are in range 1.678-1.797 Å , while the M-Cl bond lengths are in the range of 2.3932-2.4212 Å . Both sets of values are close to those found in related complexes reported in the literature [28][29][30][31][32].…”

Palladium (II) and platinum (II) complexes containing organometallic thiosemicarbazone ligands: Synthesis, characterization, X-ray structures and antitubercular evaluation

“…We found that incorporating organometallic fragments into the thiosemicarbazone scaffold resulted in a complex that exhibited moderate activity against Trypanosoma cruzi and M. tuberculosis strains. In addition, Chibale and co-workers described the synthesis and antimalarial evaluation of palladium (II), ruthenium (II) and gold (III) complexes containing ferrocenyl thiosemicarbazones [38,40,41]. In all cases, the heterobimetallic complexes exhibited moderate activity against chloroquine-susceptible (NF54) and chloroquineresistant (Dd2) Plasmodium falciparum strains.…”

Thermodynamic Investigation of Interaction Between [(η 6-p-Cymene) RuII(Acetone-N 4-Phenylthiosemicarbazone)Cl]Cl Anticancer Drug and Human Serum Albumin: Spectroscopic and Electrochemical Studies

“…Beckford and co-workers have reported the Ru(II)-arene half-sandwich complexes with TSC ligands combining the {(η 6 -p-cymene) Ru(II)} moiety with TSC derivatives as ligands and further confirmed the good anticancer activity of these complexes against different human cancer cell lines [6,7]. Smith et al demonstrated the cytotoxicity and antiparasitic activity of a series of TSC derivatives and their corresponding mononuclear and dinuclear Ru(II)-arene complexes [8,9]. Su et al have synthesized some Ru(II)-arene complexes with TSC ligands and further investigated the anticancer activities of them [10,11].…”

“…Recently, Ru(II)-arene complexes of thiosemicarbazone (TSC) with half-sandwich-type structure have emerged as novel strategies to develop promising lead Ru-based therapeutic drugs [1][2][3][4][5]. Some research has demonstrated the anticancer activity of Ru(II)-arene complexes of TSC anticancer drugs.…”