Heteroleptic Transition Metal Complexes of Eflornithine Hydrochloride Monohydrate: Synthesis, Characterization, in silico and in vitro Biological Studies Yusuf AYİPO Journal of the Turkish Chemical Society Section A Chemistry, 2022 Incessant development of resistance to drugs by microorganisms remains a major setback associated with the currently available antibiotics, thereby making imperative a continuous search for alternative candidates with improved efficacy. Previous studies have shown enhanced antimicrobial activity of some bioactive molecules upon coordination with metal ions. Thus, in this study, Cu(II), Co(II), and Ni(II) complexes of eflornithine hydrochloride monohydrate (EHM) were synthesized and probed for bactericidal activity via in vitro and in silico. The characterization results such as CHN analysis, FTIR, UV-visible magnetic susceptibility and Electrospray Ionization Mass Spectrometry (ESI-MS) reveal that EHM coordinates as a bidentate ligand to each central metal ion in the molar ratio 1:2 through O and N in the COO- and NH2 group respectively, and also suggest octahedral geometry in each complex. The physicochemical and pharmacokinetics parameters predicted in silico support the bio-applicability and safety of the complexes. From the in vitro antibacterial study, the complexes demonstrate improved activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa with an average minimum inhibitory concentration (MIC) of 0.01 mg/L similar to ciprofloxacin, compared to EHM whose MIC >1.00 mg/L. Although, not all the complexes satisfy Lipinski’s drugability rule of 5 due to their molecular weight, however, coordination with metal ions improves the biological activities of EHM and the complexes demonstrate potential for further transformation into antibiotic therapeutics.
Synthesis, characterization, in-vitro anti-inflammatory and antimicrobial screening of metal(ii) mixed diclofenac and acetaminophen complexes J. A. Obaleye, A. A. Aliyu, A. O. Rajee, K. E. Bello Bulletin of the Chemical Society of Ethiopia, 2021 Mixed ligand complexes derived from diclofenac potassium salt (Kdc) and acetaminophen (ace) has been synthesized and proposed to have a general formula [MB] where M = Co2+, Ni2+, Cu2+ and Zn2+and B = (ace)(dc)(H2O)2 except for Mn2+ complex which exists as [Mn(ace)(dc)OH2]. The complexes were characterized by solubility, melting point, conductivity, elemental analyses, UV-Vis, FT-IR spectroscopy, X-ray powder diffraction (XRPD) study and magnetic susceptibility measurement. Electronic absorption spectra data are characteristic of octahedral structures for [MB]. The IR spectra revealed a bidentate coordination mode. In acetaminophen, the nitrogen and carbonyl-O atoms of the amide group were involved while the carboxylate oxygen atoms of potassium diclofenac were used; typical of a carboxylic acid derivative. The compounds were screened for in-vitro anti-inflammatory activity by inhibition of albumin denaturation assay and antimicrobial activity against bacteria strains: Bacillus subtilis, Bacillus anthrax, Escherichia coli, Salmonella typhi and a fungus Aspergillus niger. Some of the tested compounds showed moderate anti-inflammatory activity when compared to the standard drug diclofenac potassium salt. The in-vitro antimicrobial screening revealed an increased activity of the complexes against the bacteria isolates compared to the free ligands.
 
 KEY WORDS: Metal(II) ion, NSAIDs, Anti-inflammatory activity, Diclofenac potassium salt, XRPD, Antimicrobial activity
 
 Bull. Chem. Soc. Ethiop. 2021, 35(1), 77-86.
 DOI: https://dx.doi.org/10.4314/bcse.v35i1.6
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