Nitrile‐functionalized Hg(II)‐ and Ag(I)‐N‐heterocyclic carbene complexes: synthesis, crystal structures, nuclease and DNA binding activities

Abstract

Various nitrile‐functionalized benzimidazol‐2‐ylidene carbene complexes of Hg(II) and Ag(I) were synthesized by the interaction of 1‐benzyl/1‐butyl‐3‐(cyano‐benzyl)‐3 H‐benzimidazol‐1‐ium mono/dihexafluorophosphate with Hg(OAc)2/Ag2O in acetonitrile. Two of the benzimidazolium salts were structurally characterized by single crystal X‐ray diffraction technique. Structures of reported compounds were characterized by 1 H, 13C NMR, FT‐IR, UV–visible spectroscopic techniques, and molar conductivity and elemental analyses. For bis‐benzimidazolium salt, dinuclear Hg(II)– and Ag(I)–carbene complexes were obtained. Nuclease activity and binding interactions of the synthesized benzimidazolium salts and their Ag(I)–carbene complexes with DNA were studied using agarose gel electrophoresis and, absorption spectroscopy and viscosity measurements, respectively. Ag(I)–carbene complexes showed higher DNA binding activity compared to their respective benzimidazolium salts. However, a benzimidazolium salt and two of the Ag(I) complexes showed remarkably higher nuclease activity both, in the presence and absence of an oxidizing agent. Copyright © 2012 John Wiley & Sons, Ltd.

Dose‐, time‐and lipophilicity‐dependent silver(I)–N‐heterocyclic carbene complexes: Synthesis, characterization and interaction with plasmid and Aedes albopictus DNA

“…Therefore the result suggests that the length of the chain is valuable for DNA binding. Values of K b obtained from absorption and fluorescence titrations in the present work are in reasonable agreement with those obtained from DNA titrations of similar complexes in the literature . Also the K b values of the benzimidazolium salts are sufficiently less than those of the corresponding Ag complexes available in the literature …”

Recent Developments in the Medicinal Applications of Silver-NHC Complexes and Imidazolium Salts

“…While the majority of the Ag(I)-NHC compounds that have been evaluated are mono-NHC systems, there have been many bis-NHC systems developed as well [ 47 , 48 , 49 ]. In 2014, Haque et al synthesized a series of bis-NHC systems and evaluated their antibacterial properties and subsequent nuclease activity [ 50 , 51 ]. Of the compounds synthesized and tested, 25 ( Figure 5 ) was shown to not only be the most effective antibacterial complex (MIC = 12.5 μg/mL), but also was the most efficient in promoting the cleavage of nucleic acids.…”

Synthesis, Characterization, Crystal Structures, and Catalytic C–C Coupling and Hydrosilylation Reactions of Palladium(II) Complexes Derived from CNC Pincer‐Type N‐Heterocyclic Carbenes

“…[26] Also, three medium-intensity broad bands at approximately ν = 2860, 2930, and 1100 cm -1 can be ascribed to the stretching vibrations of the C-H and C-N fragments, respectively. [28,29] In the case of the palladium(II) complexes, both the pyridine and azolium ring C=N modules are shifted to lower energy relative to the same modules of their respective salts, which is consistent with successful palladation in which the carbene carbon atoms and the pyridine nitrogen atom are involved in the coordination. [28,29] In the case of the palladium(II) complexes, both the pyridine and azolium ring C=N modules are shifted to lower energy relative to the same modules of their respective salts, which is consistent with successful palladation in which the carbene carbon atoms and the pyridine nitrogen atom are involved in the coordination.…”