Crystal structure, DNA-binding properties and antioxidative activities of a novel silver(I) inorganic polymer

In vitro investigation of biophysical interactions between Ag(I) complexes of bis(methyl)(thia/selena)salen and ct-DNA via multi-spectroscopic, physicochemical and molecular docking methods along with cytotoxicity study

Four silver(I) (Ag(I)) complexes: 1.PF₆ , 2.PF₆ , 1.ClO₄ and 2.ClO₄ of bis(methyl)thia salen (1) and bis (methyl)selena salen (2) with two different counter anions (PF₆ ^- and ClO₄ ^- ) have been investigated for DNA binding properties. In vitro interactional association between the Ag(I) complexes and ct-DNA has been examined by performing spectroscopic titrations on absorption spectrophotometer and fluorescence spectrophotometer. A competitive binding study has also been done using a fluorescence spectrophotometer with ethidium bromide as a classical intercalator. The spectroscopic methods revealed a major groove. Viscometry and agarose gel electrophoresis experiments have also been performed as physicochemical methods to confirm the binding of complex molecules with DNA. Molecular docking analysis has been executed to obtain the theoretical insight into the mode of binding. The docking study demonstrated the major groove binding of all four complexes to the DNA with electrostatic metal-phosphate interactions (between the metal and the backbone of DNA) and hydrophobic interactions. Cytotoxicity of the complexes has been studied on the Human Fibroblast foreskin (HFF) cell line. The cytotoxicity results showed positive gesture for moving ahead to the next level of screening; the values were above 10 μM which are appreciated for the normal cell lines.

Synthesis, structure, fluorescence, electrochemical, and antioxidant studies of a new silver(I) complex with 2,6-bis(N-methylbenzimidazol-2-yl)pyridine

A new silver(I) complex of the type [Ag2(mbbp)2](pic)2·DMF·CH3OH [mbbp = 2,6-bis( N-methylbenzimidazol-2-yl)pyridine] is synthesized and analyzed using a range of spectroscopic and crystallographic techniques. This compound contains cationic Ag2(mbbp)2 dimers, in which the crossed eight-shaped structure is formed by two mbbp ligands bridging two silver(I) centers and Ag–Ag bonds. Two-dimensional supramolecular networks of the silver(I) complex are connected by π···π interactions and hydrogen bonds. Hirshfeld analyses are performed to support the aforementioned intermolecular interactions. The effect of π···π stacking interactions on the fluorescence properties of the complex is investigated. Cyclic voltammetry indicates two irreversible redox processes. In addition, an antioxidant assay in vitro demonstrates that the silver(I) complex displays excellent scavenging activity toward hydroxyl radicals.

Synthesis, crystal structure, fluorescence and antioxidant properties of a binuclear Ag(I) complex based on the SPPh3 ligand

The binuclear silver(I) complex [Ag2(η2-SPPh3)2(SPPh3)2](BF4)2 has been synthesized. Crystal analysis shows the coordination sphere around Ag(I) can be described as a three-coordinated slightly distorted planar triangular configuration with both monodentate and monoatomic bidentate bridging coordination modes for the SPPh3 ligand. The fluorescence properties of free SPPh3 and the Ag(I) complex have been studied in the solid state. The Ag(I) complex shows quasi-reversible Ag+/Ag pairs in its electrochemistry and has significant antioxidant activity against hydroxyl radicals.

A new modification of [Ag4Br4(PPh3)4]: synthesis, structure and properties

A new modification of the homometallic silver(I) cluster [Ag4Br4(PPh3)4] has been prepared and characterized by elemental analysis, UV/Vis and IR spectroscopy, and X-ray crystallography. The tetramer shows a polycyclic structure with a chair conformation. The bromine atoms adopt μ 2- and μ 3-bridging modes. The shortest Ag–Ag distance in the cluster is 3.159(2) Å, which indicates significant Ag–Ag interactions. A supramolecular structure is arranged by hydrogen bonds (C–H···Br). Cyclic voltammograms of the cluster indicate a quasi-reversible Ag+/Ag couple. The fluorescence properties of the ligand and the Ag(I) cluster were studied in the solid state. The emission peaks of the Ag(I) cluster are attributed to ligand-centered luminescence.

Ag(i) bipyridyl coordination polymers containing functional anions

Traditional polymeric silver–bipyridyl complexes with the non-traditional twist of anions from functional organic molecules; diclofenac, salicylic acid and azo dyes.