Rhodium, Iridium, and Ruthenium Half-Sandwich Picolinamide Complexes as Anticancer Agents

Abstract

Novel rhodium, iridium, and ruthenium half-sandwich complexes containing (N,N)-bound picolinamide ligands have been prepared for use as anticancer agents. The complexes show promising cytotoxicities, with the presence, position, and number of halides having a significant effect on the corresponding IC50 values. One ruthenium complex was found to be more cytotoxic than cisplatin on HT-29 and MCF-7 cells after 5 days and 1 h, respectively, and it remains active with MCF-7 cells even under hypoxic conditions, making it a promising candidate for in vivo studies.

Synthesis, Spectral, X‐Ray Diffraction, DFT, and Nematicidal Activity of Mixed Ligand Complexes of Ethyl 2‐(2‐Hydroxybenzylidine)‐Hydrazine Carboxylate and 1,10‐Phenanthroline with Some Transition Metals

“…In addition, the presence of nitrogen and oxygen donor atoms in the complexes makes these compound highly effective as carcinostatic, antitumor, and antiviral agents, and makes them interesting models for metalloenzymes, stereospecific catalysts for oxidation, reduction, and hydrolysis. They also show biological activity …”

Increasing anti-cancer activity with longer tether lengths of group 9 Cp* complexes

“…24 We have previously reported a range of iridium picolinamide complexes that inhibit Trx-R, with IC 50 values in the nanomolar range. 19,25 This prompted us to investigate whether these novel complexes 2b, 2c, 2d, 3a and 3b reported here are also able to inhibit Trx-R activity. Significantly, all the active rhodium and iridium functionalised Cp ‡ dimers were found to be potent Trx-R inhibitors with IC 50 values in the nanomolar or low micromolar range (Table 3 and Figure S1).…”

Bis‐picolinamide Ruthenium(III) Dihalide Complexes: Dichloride‐to‐Diiodide Exchange Generates Single trans Isomers with High Potency and Cancer Cell Selectivity

“…[41,42] More recently,G lazer and co-workers have compared the activities of cis-[Ru(bpy) 2 Cl 2 ]( bpy = 2,2'-bipyridine) with trans-[Ru(qpy)Cl 2 ]( qpy = 2,2':6',2'':6'',2'''-quaterpyridine), finding the trans isomer to be 7-10 times more active than the cis isomer. [43] This propensityf or the formation of different isomersi so ne of the reasonst hat there has been much effort dedicated to the synthesis and development of transition-metal-based candidates that are based on the molecular architectures associatedw ithM -arene, [44][45][46][47][48][49][50][51] MCp* [47,[52][53][54][55][56][57] and ferrocened erivatives. [58,59] The complexation of ruthenium to picolinamidel igandsi so f interestb ecause of its relevance to previously reported metalion peptide chemistry and the possibility of different ligand bindingm odes that can potentially alter the biological activity of the complexes.…”