Organometallic dithiolene complexes of benzenedithiolate analogues with π-coordinating and π-interacting Cp* ligand

Targets, Mechanisms and Cytotoxicity of Half-Sandwich Ir(III) Complexes Are Modulated by Structural Modifications on the Benzazole Ancillary Ligand

Cancers are driven by multiple genetic mutations but evolve to evade treatments targeting specific mutations. Nonetheless, cancers cannot evade a treatment that targets mitochondria, which are essential for tumor progression. Iridium complexes have shown anticancer properties, but they lack specificity for their intracellular targets, leading to undesirable side effects. Herein we present a systematic study on structure-activity relationships of eight arylbenzazole-based Iridium(III) complexes of type [IrCl(Cp*)], that have revealed the role of each atom of the ancillary ligand in the physical chemistry properties, cytotoxicity and mechanism of biological action. Neutral complexes, especially those bearing phenylbenzimidazole (HL1 and HL2), restrict the binding to DNA and albumin. One of them, complex 1[C,NH-Cl], is the most selective one, does not bind DNA, targets exclusively the mitochondria, disturbs the mitochondria membrane permeability inducing proton leak and increases ROS levels, triggering the molecular machinery of regulated cell death. In mice with orthotopic lung tumors, the administration of complex 1[C,NH-Cl] reduced the tumor burden. Cancers are more vulnerable than normal tissues to a treatment that harnesses mitochondrial dysfunction. Thus, complex 1[C,NH-Cl] characterization opens the way to the development of new compounds to exploit this vulnerability.

Structural diversity of bimetallic rhodium and iridium half sandwich dithiolato complexes

Subtle changes in the structure of the backbone can lead to profound differences in the binding modes of dithiolato ligands in rhodium and iridium half sandwich complexes.

Bis(tetra-n-butyl-ammonium) bis-(5,6-dicyano-pyrazine-2,3-dithiol-ato-κS,S')palladium(II)

In the title complex, (C(16)H(36)N)(2)[Pd(C(6)N(4)S(2))(2)], the centrosymmetric dianion is planar, with an r.m.s. deviation of 0.034 (8) Å. The Pd(II) atom, lying on an inversion center, has a square-planar coordination geometry, with Pd-S bond lengths of 2.276 (3) and 2.294 (3) Å.