Di- and polynuclear silver(I) saccharinate complexes of tertiary diphosphane ligands: synthesis, structures, in vitro DNA binding, and antibacterial and anticancer properties

Abstract

A series of new silver(I) saccharinate (sac) complexes, [Ag2(sac)2(μ-dppm)H2O]·H2O (1), {[Ag2(μ-sac)2(μ-dppe)]·3H2O·CH2Cl2} n (2), [Ag2(μ-sac)2(μ-dppp)] n (3), and [Ag(sac)(μ-dppb)] n (4) [dppm is 1,1-bis(diphenylphosphino)methane, dppe is 1,2-bis(diphenylphosphino)ethane, dppp is 1,3-bis(diphenylphosphino)propane, and dppb is 1,4-bis(diphenylphosphino)butane], have been synthesized and characterized by C, H, N elemental analysis, IR spectroscopy, (1)H NMR, (13)C NMR, and (31)P NMR spectroscopy, electrospray ionization mass spectrometry, and thermogravimetry-differential thermal analysis. Single-crystal X-ray studies show that the diphosphanes act as bridging ligands to yield a dinuclear complex (1) and one-dimensional coordination polymers (2 and 4), whereas the sac ligand adopts a μ2-N/O bridging mode in 2, and is N-coordinated in 1 and 4. The interaction of the silver(I) complexes with fish sperm DNA was investigated using UV-vis spectroscopy, fluorescence spectroscopy, and agarose gel electrophoresis. The binding studies indicate that the silver(I) complexes can interact with fish sperm DNA through intercalation, and complexes 1 and 3 have the highest binding affinity. The gel electrophoresis assay further confirms the binding of the complexes with the pBR322 plasmid DNA. The minimum inhibitory concentrations of the complexes indicate that complex 1 exhibits very high antibacterial activity against standard bacterial strains of Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus, being much higher than those of AgNO3, silver sulfadiazine, ciprofloxacin, and gentamicin. Moreover, complexes 1-3 exhibit very high cytotoxic activity against A549 and MCF-7 cancer cell lines, compared with AgNO3 and cisplatin. The bacterial and cell growth inhibitions of the silver(I) complexes are closely related to their DNA binding affinities.

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

“…typhi and S . aureus , respectively . Silver nitrate is the standard and most popular silver salt in wound therapy where it is applied for prophylaxis in topical burns as a 0.5% silver salt solution .…”

Silver coordination compounds: A new horizon in medicine

“…In another study, a series of mixed silver saccharinate complexes was prepared in order to check the effects on their biological activity following an increase in the spacer length of bidentate diphenylphosphines with a general formula Ph 2 P(CH 2 ) n PPh 2 (n = 1-4) [66]. X-ray analysis evidenced that the diphosphines can act both as bridging ligands to yield a dinuclear complex in the case of dppm (n = 1), or as one-dimensional coordination polymers (dppe, n = 2, dppb, n = 4), whereas the saccharinate can behave both as an N/O bridging ligand or an N-coordinating donor.…”

Ni(II), Cu(II), Mn(II), and Fe(II) Metal Complexes Containing 1,3-Bis(diphenylphosphino)propane and Pyridine Derivative: Synthesis, Characterization, and Antimicrobial Activity

“…e bands between 2850-2923 and 3020-3046 cm −1 are due to the absorption of the phenyl and CH 2 groups [27]. From these discussions, it is concluded that DPPP coordinates to the metal ions in a bidentate mode through phosphorus atoms.…”

“…ese results confirm that the pyridine groups are coordinated to the metal ions as a monodentate through the N-atom. e very strong band for the P-C vibration of free forms of phosphine ligand displays a shift from 690 cm −1 to a lower wave number (681-694 cm −1 ) [27].…”