Synthesis, characterization, antimicrobial screening and DNA binding of novel silver(I)–thienylterpyridine and silver(I)–furylterpyridine complexes

Abstract

Six new silver(I) complexes, [(AgL1) 2 ](ClO 4 ) 2 (1), [(AgOTfL1) 2 ] (2), [(AgO 2 CF 3 L1) 2 ] (3), [AgL2](ClO 4 ) 2 (4), [(AgOTfL2) 2 ] (5) and [(AgO 2 CF 3 L2) 2 ] (6), were synthesized by reaction of 4′-(2-thienyl)-2,2′;6′,2″-terpyridine (L1)or 4′-(2-furyl)-2,2′;6′,2″-terpyridine (L2) with the respective silver salts, i.e. AgClO 4 , AgOTf or AgTFA. The complexes are dinuclear of the type Ag 2 L 2 in which the two ligands utilize the pyridinyl N atoms from the central rings and one of the peripheral rings to coordinate to one of the silver(I) centres while the remaining pyridinyl N atoms coordinate to the second silver(I) centre. Complexes 2 and 5 have the trifluoromethanesulfonate anion remotely coordinating via a single O atom while complex 3 has the trifluoroacetate anion coordinating to a single silver(I) centre in a bidentate mode. The perchlorate anion in complex 4 is excluded from the silver(I) coordination sphere.All complexes demonstrate moderate to high antimicrobial activity against the Gram-negative bacteria Escherichia coli and Salmonella typhimirium and the fungus Candida albicans. Complexes 1-6 interact strongly with salmon testes DNA as indicated by the steady increase in the relative viscosity of DNA solutions with increasing concentration of the silver(I) complexes and the relatively large intrinsic binding constants measured. There was substantial hyperchromism and hypsochromism recorded in solutions of complexes 1-6 with increasing concentration of salmon testes DNA. Complexes 1-6 interact with DNA via intercalation, and groove and external binding.

Quinoline Functionalized Schiff Base Silver (I) Complexes: Interactions with Biomolecules and In Vitro Cytotoxicity, Antioxidant and Antimicrobial Activities

“…The resulting geometry is distorted pseudo tetrahedral with the bond angles around the Ag(I) center being 99.86 (10), 105.57 (10), 162.01 (10), and 175.69 (9)°. A similar mode of coordination has been reported [ 50 ]. The asymmetric unit of Q14 has a molecule of the ligand, an Ag(I) metal center, a trifluoromethanesulfonate molecule and a molecule of water.…”

Crystal structure of chlorido-(η 5-pentamethylcyclopentadienyl)-(4-chloro-4-pyridyl-2,2′:6′,2′′-terpyridine-κ2N,N′) rhodium(III) hexaflourophosphate, C31H29Cl2F6N3PRh

“…One of the most commonly used ligands are the nitrogen containing ligands. In organometallic chemistry, nitrogen containing ligands can coordinate with various transition metals because of the inherent lone pair of electrons [8][9][10][11][12][13]. Thus N-containing ligands are a crucial component in coordination chemistry.…”

“…As an N-,N′-N′′-tridentate ligand the 2,2′:6′,2′′-terpyridine ligand plays an important role in coordination chemistry with three coordination sites and low LUMO. Terpyridine and its derivatives are among the typical pincer ligands and/or non-innocent ligands in transition metal catalysis [8][9][10][11][12][13].…”

“…The multidentate terpyridine based ligands have been extensively investigated, modified and utilized in various works in organic and inorganic supramolecular chemistry [8][9][10][11][12][13]. This is due to the relative ease of synthesizing and modifying the terpyridine moiety, with π-stacking ability, directional hydrogen-bonding, conjugated aromatic cores and coordination properties amongst other structural features [8][9][10][11][12][13].…”

4′-(N-(Propan-1,2-dienyl)pyrrol-2-yl)-2,2′:6′,2″-terpyridine

“…In particular, terpyridines that contain a five membered heterocycle, such as furan [2] or thiophene [3], have attracted a lot of attention. In fact, they can be used as intermediates in the preparation of materials for solar cells [4] or nanoparticles [5], as biological probes [6], as ligands in catalysis [7], as antimicrobial agents [8], as electrochromic materials [9] or as chromophores [10], to name just a few applications. Although a little less studied, terpyridines that include a pyrrole ring have also been a subject of interest.…”