Mono and binuclear cobalt(II) mixed ligand complexes containing 1,10-phenanthroline and adenine using 1,3-diaminopropane as a spacer: synthesis, characterization, and antibacterial activity investigations

Abstract

Background Coordination compounds, in particular cobalt(II) mixed ligand complexes containing 1,10-phenantroline, have drawn the attention of many investigators as some of them are showing antimicrobial activities. Result Herein, we report three novel mixed ligand complexes of cobalt(II) having the formulae [Co(L1)2(H2O)2]Cl2, [Co(L1)2(L2)(H2O)]Cl2 and [Co2(L1)4(L2)2(L3)]Cl4 (L1 = 1,10-phenanthroline, L2 = adenine, L3 = 1,3-diaminepropane) were synthesized and characterized by elemental analysis, conductivity measurement, infrared, and UV-Vis spectroscopic techniques. Octahedral geometries are proposed to all the complexes. In vitro antibacterial activities of the ligands, salt, and metal complexes were tested on four pathogenic bacteria (Staphylococcus aureus, Salmonella typhus, Escherichia coli, and Staphylococcus epidermis) using disc diffusion method. Conclusions It is interesting to note that the newly synthesized cobalt(II) complexes are active against gram negative bacteria (Escherichia coli and Klebsiella pneumoniae) even though cobalt(II) complexes are well known for their activity against gram positive bacteria.

Cytotoxic mixed-ligand complexes of Cu(II): A combined experimental and computational study

“…These indicates that the C=C and C=N bond order decreased the ligand coordination to the Cu(II) metal center. On the other hand, the decrease in their intensity indicates the formation of rigid and symmetric structure to the Cu(II) metal center ( Abebe et al, 2020 ). More importantly, the appearance of bands (experimental/calculated) at 509/452 cm −1 and 422/423 cm −1 ( Figure 1 ) are associated with the formation of Cu-O and Cu-N bonds, respectively.…”

Synthesis, structural investigations, and in vitro biological activity of Co(II) and Fe(III) mixed ligand complexes of 1,10‐phenanthroline and 2,2′‐bipyridine

“…It is important to note that 1,10‐phenanthroline and 2,2′‐bipyridine have high antibacterial activities against tested bacteria; however, they could not be used for medicinal applications directly due to cytotoxicity caused by its strong chelating nitrogen atoms binds with biometals and inhibiting metalloenzymes (Abebe et al, 2018). The most common scenario to minimize their toxicity and benefit from their antibacterial privilege is coordinating them with metal ions (Abebe & Hailemariam, 2016; Abebe et al, 2017, 2020; Tigineh et al, 2019, 2021; Tamiru et al, 2019). The observed change in antibacterial activity of complexes compared to the ligands can be explained based on Overton's concept of cell permeability (Anjaneyulu & Rao, 1986) and Tweedy's chelation theory (Tweedy, 1964).…”

“…Previously, our group also reported mono‐ and binuclear mixed ligand complexes with those metals having redox potentials such as Iron(III) (Tigineh et al, 2021), cobalt(II) (Abebe et al, 2020, 2021; Atakilt et al, 2019; Tigineh & Abebe, 2019; Tamiru et al, 2019), copper(II) (Abebe et al, 2017), and ruthenium(III) (Abebe & Hailemariam, 2016) with different ligand combinations for biological applications and obtained promising antibacterial results. However, to our knowledge, there is no report yet with the present form of combination from our group and elsewhere.…”

Reactions of MoCl5 and MoO2Cl2 with Succinimide, 1, 4-Diaminobutane, 3-Methylpyridine, 1, 3-Diaminopropane, Pyrazole and 1- Methylpyrrolidine in Tetrahydrofuran

“…It is used as precursor for preparation of pharmaceuticals, organic chemicals and agrochemicals. It is used 27 in the synthesis of heterocycles used in coordination complexes and textile finishing. It is a potential inhibitor 28,29 against neoplasia and ornithine decarboxylase enzyme protein on rat urinary bladder carcinogenesis.…”

“…It is part of cefepime 42 : broad-spectrum cephalosporin antibiotic capable to treat bacteria causing pneumonia, infections of the skin and urinary tract. Desired properties 27,43 on transition metals for particular applications can be incorporated by coordination of metals with certain ligands. It involves modification of properties, like stability of oxidation states, electrophilic/nucleophilic properties and solvophilicity of the metal ions.…”