Rhenium-Pyrazolyl-Based Figure-Eight- and Z-Shaped Metallocycles: Self-Assembly, Solid-State Structures, Dynamic Properties in Solution, and Competitive Ligand-Induced Supramolecular Transformations into Rhenium-Pyridyl/-Benzimidazolyl/-Phosphine-Based Metallocycles/Acyclic Complexes.

Rhenium(I)tricarbonyl core-based heteroleptic "figure-eight"- and Z-shaped metallocycles (-) of the general formula -[{(CO)Re(μ-L)Re(CO)}(dppz)] were self-assembled from Re(CO), H-L (H-L = 5,8-dihydroxy-1,4-naphthaquinone (H-dhnq) for ; 1,4-dihydroxy-9,10-anthraquinone (H-dhaq) for ; 6,11-dihydroxy-5,12-naphthacenedione (H-dhnd) for ; 2,2'-bisbenzimidazole (H-bbim) for ), and bis(4-((pyrazolyl)methyl)phenylmethane) (dppz) via one-pot coordination-driven synthetic approach. The molecular structures of and were unambiguously confirmed by single-crystal X-ray diffraction (SC-XRD) methods. The metallocycles in the DMSO solution exist as an acyclic dinuclear-DMSO adduct of the general formula -[{(CO)Re(μ-L)Re(CO)}(DMSO)] (, L = dhnq; , L = dhaq; , L = dhnd; , L = bbim) and dppz, which are in dynamic equilibrium.

Trinuclear rhenium(I)-based metallocages as anticancer agents towards human cervical cancer cells.

The first examples of spherical-shaped trinuclear rhenium(I) organometallic cages displaying cytotoxic, antimetastatic, antiproliferative and DNA-damaging behavior towards a human cervical (HeLa) cancer cell line are reported. The compact design of the metallocages facilitates their interactions with biosystems leading to comparable efficiency to that of the commonly used anticancer drug cisplatin.

Self-assembly of a new class of rhenium(I)-based double stranded dinuclear monohelicates with their photophysical and electrochemical studies.

A new class of double stranded dinuclear monohelicates, -[{Re(CO)-(μ-L)-Re(CO)}L] (1-4), were self-assembled from Re(CO), a rigid bischelating donor (H-L: 1,4-dihydroxybenzoquinone (H-dhbq) for 1 and 3; 2,5-pyrazine dicarboxylic acid (H-pydc) for 2 and 4) and a flexible bis(monodentate) pyrazolyl N donor L (L = bis(4-((pyrazolyl)methyl)phenyl)methane for 1 and 2; L = bis(4-((pyrazolyl)methyl)phenyl)methanone for 3 and 4) in mesitylene. Metallomacrocycle 1 was confirmed by single crystal X-ray crystallography. Although these helicates contain two organic ligand strands, only one strand is arranged in a helical fashion, which is an unprecedented form in the helicate architecture.