[Ag(L)NO₃] Complexes with 2-Benzoylpyridine-Derived Hydrazones: Cytotoxic Activity and Interaction with Biomolecules

Abstract

Complexes [Ag(H2BzPh)NO3] (1), [Ag(H2BzpCH3Ph)NO3] (2), [Ag(H2BzpClPh)NO3] (3), and [Ag(H2BzpNO2Ph)NO3] (4) were synthesized with 2-benzoylpyridine benzoylhydrazone (H2BzPh) and its para-methyl-benzoylhydrazone (H2BzpCH3Ph), para-chloro-benzoylhydrazone (H2BzpClPh), and para-nitro-benzoylhydrazone (H2BzpNO2Ph) derivatives. Experimental data indicate that the nitrate ligand binds more strongly to the silver center through one of the oxygen atoms, whereas the second oxygen atom from nitrate and the hydrazone oxygen makes much weaker interactions with the metal. Dissociation of nitrate most probably occurs in solution and in biological media. Interestingly, theoretical calculations suggested that when dissociation of the nitrate takes place, all bond orders involving the metal and the atoms from the hydrazone ligand increase significantly, showing that the bonding of nitrate results in the weakening of all other interactions in the metal coordination sphere. Upon complexation of the hydrazones to silver(I), cytotoxicity against B16F10 metastatic murine melanoma cells increased in all cases. Complexes (1–3) proved to be more cytotoxic than cisplatin. All compounds were more cytotoxic to B16F10 cells than to nontumorigenic murine Melan-A melanocyte cells. Interestingly, the selectivity index (SI = IC50 non-malignant cells/IC50 tumor cells) of complex (1), SI = 23, was much higher than that of the parent hydrazone ligand, SI = 9.5. Studies on the interactions of complexes (1–3) with DNA suggested that although (1–3) interact with calf thymus DNA by an intercalative mode, direct covalent binding of silver(I) to DNA probably does not occur. Complexes (1–3) interact in vitro with human serum albumin indicating that these compounds could be transported by albumin.

Self-Assembly by Tridentate or Bidentate Ligand: Synthesis and Vapor Adsorption Properties of Cu(II), Zn(II), Hg(II) and Cd(II) Complexes Derived from a Bis(pyridylhydrazone) Compound

“…So far, hydrazone-based metal complexes have received considerable attention from chemists in many applications such as chromogenic reagents in the spectrophotometric determination of transition-metal ions, metal extracts and biologically active compounds [ 9 ]. They have also been demonstrated to possess diverse pharmacological properties [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ], catalytic properties [ 18 , 19 ], adsorption properties [ 20 , 21 ], electrochemical properties [ 22 ], luminescent properties [ 23 , 24 ], etc.…”

Synthesis, Spectroscopy, Single-Crystal Structure Analysis and Antibacterial Activity of Two Novel Complexes of Silver(I) with Miconazole Drug

“…A review of the literature shows that the slight shifts to the higher field for silver(I) complexes compared to the free ligand are not surprising. This indicates the effect of coordination of the ligand through the nitrogen atom of the imidazole ring with Ag(I) ions, only slightly reflected in the peripheral ring protons [ 52 , 53 , 54 , 55 ]. Spectra of the silver(I) complexes of miconazole 3 and 4 are presented in Supplementary Figure S1 .…”

New Silver(I) Coordination Compound Loaded into Polymeric Nanoparticles as a Strategy to Improve In Vitro Anti-Helicobacter pylori Activity

“…The new silver(I) complex, compound 1, was synthesized by the reaction of AgNO 3 with 2pyridinecarboxaldehyde-N(4)-phenylthiosemicarbazone (L 1 ) in a 1:2 molar ratio (Figure 1). Compound 1 was characterized by elemental analysis and FT-IR and 1 H and 13 C NMR spectroscopy techniques (Supporting Information). The elemental analysis data validated the proposed formulation.…”

“…Fourier transform infrared (FT-IR) spectra were recorded using a PerkinElmer Spectrum 200 spectrometer in the range of 4000−400 cm −1 using KBr pellets. 1 H and 13 C nuclear magnetic resonance (NMR) spectra were acquired on a 14.1 T Avance III HD spectrometer at 298 °K (Bruker, Billerica, MA).…”