Synthesis, anticancer, and cytotoxic activities of some mononuclear Ru(II) compounds Original Research Article

The synthesis and characterization of ruthenium compounds (Ru1–Ru12) of the type [Ru(S)2(K)], (where S = 1,10-phenanthroline/2,2′-bipyridine and K = itsz, MeO-btsz, 4-Cl-btsz, 2-Cl-btsz, 2-F-btsz, hfc and itsz = isatin-3-thiosemicarbazone, MeO-btsz = 1-(4′-methoxy-benzyl)-thiosemicarbazone, hfc = 2-{[3-chloro-4-fluoro-phenylimino]methyl}phenol, 4-Cl-btsz = 1-(4′-chlorobenzyl)-thiosemicarbazone, 2-Cl-btsz = 1-(2′-chloro benzyl)-thiosemicarbazone, 2-F-btsz = 1-(2′-fluorobenzyl)-thiosemicarbazone) are described. These ligands form bidentate octahedral ruthenium compounds. The title compounds were subjected to in vivo anticancer activity against a transplantable murine tumor cell line Ehrlich’s Ascites Carcinoma (EAC) and in vitro cytotoxic activity against human cancer cell line Molt 4/C8, CEM and murine tumor cell line L1210. Ruthenium compounds (Ru1–Ru12) showed promising biological activity especially in decreasing tumor volume and viable ascites cell counts. Treatment with these compounds prolonged the life span of mice bearing EAC tumor by 10–43%. In vitro evaluation of these ruthenium compounds revealed cytotoxic activity from 0.24 to 27 μM against Molt 4/C8, 0.27 to 48 μM against CEM, and 0.94 to 248 μM against L1210. Their ligands alone failed to show cytotoxic activity at the concentrations tested (68–405 μM).