Monodentately-coordinated bioactive moieties in multimodal half-sandwich organoruthenium anticancer agents

Metallodrugs have a central role in the treatment and diagnosis of diseases. To overcome potential toxicity and equip metal-based anticancer agents with biological activity, the choice of the ligands coordinated to the metal center is essential. A recent strategy to address the shortcomings of current drugs and improve their targeted properties, is to introduce bioactive ligands, which may result in synergistic activity between the metal center and the ligand system. In this review, we discuss such efforts in the development of Ru half-sandwich compounds, a class of promising anticancer agents which have been widely studied. We explore here strategies to introduce monodentately-coordinated bioactive moieties into such metal complexes by a variety of design concepts and review their potential as multimodal anticancer agents.