Binding Modes and Selectivity of Ruthenium Complexes to Human Telomeric DNA G-Quadruplexes.

Metal complexes constitute an important class of DNA binders. In particular, a few ruthenium polyazaaromatic complexes are attractive as "light switches" because of their strong luminescence enhancement upon DNA binding. In this paper, a comprehensive study on the binding modes of several mononuclear and binuclear ruthenium complexes to human telomeric sequences, made of repeats of the d(TTAGGG) fragment is reported.

A General Copper-based Photoredox Catalyst for Organic Synthesis: Scope, Application in Natural Product Synthesis and Mechanistic Insights.

Organic transformations can broadly be classified into four categories including cationic, anionic, pericyclic and radical reactions. While the last category has been known for decades to provide remarkably efficient synthetic pathways, it has long been hampered by the need for toxic reagents, which considerably limited its impact on chemical synthesis. This situation has come to an end with the introduction of new concepts for the generation of radical species, photoredox catalysis - which simply relies on the use of a catalyst that can be activated upon visible light irradiation - certainly being the most efficient one.

Synthesis and photophysical studies of a multivalent photoreactive Ru-calix[4]arene complex bearing RGD-containing cyclopentapeptides.

Photoactive ruthenium-based complexes are actively studied for their biological applications as potential theragnostic agents against cancer. One major issue of these inorganic complexes is to penetrate inside cells in order to fulfil their function, either sensing the internal cell environment or exert a photocytotoxic activity. The use of lipophilic ligands allows the corresponding ruthenium complexes to passively diffuse inside cells but limits their structural and photophysical properties.

A General Copper Catalyst for Photoredox Transformations of Organic Halides.

A broadly applicable copper catalyst for photoredox transformations of organic halides is reported. Upon visible light irradiation in the presence of catalytic amounts of [(DPEphos)(bcp)Cu]PF and an amine, a range of unactivated aryl and alkyl halides were shown to be smoothly activated through a rare Cu(I)/Cu(I)*/Cu(0) catalytic cycle. This complex efficiently catalyzes a series of radical processes, including reductions, cyclizations, and direct arylation of arenes.

Photochemistry of ruthenium(ii) complexes based on 1,4,5,8-tetraazaphenanthrene and 2,2'-bipyrazine: a comprehensive experimental and theoretical study.

Polyazaaromatic ruthenium(ii) complexes have been largely studied over the last decades, particularly in the scope of the biological applications, for the development of new diagnostic and phototherapeutic agents. In this context, Ru(ii) complexes able to react with biomolecules upon excitation are of great interest. Photo-oxidizing Ru(ii) complexes based on π-deficient ligands, such as bpz (2,2'-bypyrazine) and TAP (1,4,5,8-tetraazaphenathrene), were designed to allow a photo-induced electron transfer (PET) to take place in presence of biomolecules, thanks to their highly photo-oxidizing MLCT state.