Three new dinuclear nickel(II) complexes with amine pendant-armed ligands: Characterization, DFT study, antibacterial and hydrolase-like activity
摘要:
Herein, we report the synthesis and characterization of three new Ni(II) complexes, namely: [Ni-2(H2LEt)(mu-OAc)(2)(H2O)]BPh4 center dot ClO4 (1), (H2LEt = 2-[(N-benzyl-N-2-pyridyl methylamine)]-4-methyl-6-[N-2(pyridylmethyl) aminomethyl)]-6((2-aminoethyl)amino)methyl phenol); [Ni-2(H(2)LProp)(mu-OAc)(2)(H2O)](ClO4)(2) (2), (H(2)LProp = 2-[(N-benzyl-N-2-pyridylmethylamine)]-4-methyl-6-[N-(2-pyridylmethyl)aminomethyl]-6-((2-aminopropyl) amino)methylphenol); and [Ni-2(LBut)(mu-OAc)(2)(H2O)](HCl)(2) (3), (LBut = 2-[(N-benzyl-N-2-pyridylmethylamine)]-4-methyl-6-[N-(2-pyridylmethyl)aminomethyl]-6-((2-aminobuthyl) amino)methylphenol). All of them were characterized through spectroscopic techniques (elemental analysis, IR, UV-Vis spectroscopy), ESI-MS, electrochemistry and potentiometric titration. Density functional theory (DFT) was used to better understand the electronic and molecular structure of these complexes. The hydrolytic activity of complexes 1-3 towards the 2,4-BDNPP substrate was analyzed and complex 2 presented the highest catalytic efficiency (k(cat)/K-M) of the three, possibly due to a greater interaction with the substrate. The complexes were also screened for their antibacterial activities using both Gram-positive and Gram-negative bacterial strains by minimum inhibitory concentration and minimum bactericidal concentration methods.