Syntheses, characterization, and biological activity of novel mono- and binuclear transition metal complexes with a hydrazone Schiff base derived from a coumarin derivative and oxalyldihydrazine

Exploring New Schiff Bases: Synthesis, Characterization, and Multifaceted Analysis for Biomedical Applications

The current work aims to generate novel Schiff bases by reacting substituted aldehydes with amine derivatives catalyzed by a natural acid. The developed compounds underwent diverse physicochemical analyses including liquid chromatography-mass spectrometry, Fourier transform infrared spectroscopy, scanning electron microscopy, 1H- and 13C-nuclear magnetic resonance, and X-ray diffraction. Furthermore, differential thermogravimetric, thermogravimetric, and differential thermal analysis techniques were employed in a nitrogen-free environment to determine kinetic parameters. These data were then used in model-free isoconversional methods (e.g., Friedman, Kissinger-Akahira-Sunose, and Flynn-Wall-Ozawa). The Schiff bases were evaluated for their in vitro and in silico α-amylase inhibitory activity. Schiff base-2 displayed the highest inhibition compared with the reference drug acarbose. In comprehensive MTT assay cytotoxicity investigations, both Schiff bases showed strong anticancer capabilities against the human lung cancer cell line (A549). Moreover, this study demonstrated effectiveness of synthetic compounds in screening Caenorhabditis elegans for anti-Alzheimer's and stress resistance properties. The simplicity of its biology allowed precise evaluation of the effect of compounds on neuronal function and stress response. This research enhances drug discovery efforts for Alzheimer's and stress-related disorders, potentially improving patient outcomes.

Iron-Imine Cocktail in Drug Development: A Contemporary Update

Organometallic drug development is still in its early stage, but recent studies show that organometallics having iron as the central atom have the possibility of becoming good drug candidates because iron is an important micro-nutrient, and it is compatible with many biological systems, including the human body. Being an eco-friendly Lewis acid, iron can accept the lone pair of electrons from imino(sp2)-nitrogen, and the resultant iron-imine complexes with iron as a central atom have the possibility of interacting with several proteins and enzymes in humans. Iron-imine complexes have demonstrated significant potential with anticancer, bactericidal, fungicidal, and other medicinal activities in recent years. This article systematically discusses major synthetic methods and pharmacological potentials of iron-imine complexes having in vitro activity to significant clinical performance from 2016 to date. In a nutshell, this manuscript offers a simplistic view of iron complexes in medicinal inorganic chemistry: for instance, iron is presented as an "eco-friendly non-toxic" metal (as opposed to platinum) that will lead to non-toxic pharmaceuticals. The abundant literature on iron chelators shows that many iron complexes, particularly if redox-active in cells, can be quite cytotoxic, which can be beneficial for future targeted therapies. While we made every effort to include all the related papers, any omission is purely unintentional.

Comprehensive Review on Medicinal Applications of Coumarin-Derived Imine-Metal Complexes

Coumarins are fused six-membered oxygen-containing benzoheterocycles that join two synthetically useful rings: α-pyrone and benzene. A survey of the literature shows that coumarins and their metal complexes have received great interest from synthetic chemists, medicinal scientists, and pharmacists due to their wide spectrum of biological applications. For instance, coumarin and its derivatives have been used as precursors to prepare a large variety of medicinal agents. Likewise, coumarin-derived imine-metal complexes have been found to display a variety of therapeutic applications, such as antibacterial, antifungal, anticancer, antioxidant, anthelmintic, pesticidal, and nematocidal activities. This review highlights the current synthetic methodologies and known bioactivities of coumarin-derived imine-metal complexes that make this molecule a more attractive scaffold for the discovery of newer drugs.

Synthesis, Characterization and Biological Activity of Mixed Ligand (Imine of Benzidine and 1,10-Phenanthroline) Complexes with Fe(II), Co(II), Ni(II) and Cu(II) Ions

In this paper, binuclear metal complexes of the metal ions Fe(II), Co(II), Ni(II) and Cu(II) were synthesized by the reaction of the primary ligand (imine of benzidine) (H2L) and the secondary ligand (1,10-phenanthroline) (L`) with these metal ions in a molar ratio of 1:2:2, respectively. The complexes were characterized using CHN elemental analysis, FT-IR, UV-Vis, magnetic susceptibility, molar conductivity, 1H NMR, and TGA-DTA thermogravimetric analysis. According to the results obtained from the elemental analysis and spectral measurements where complexes of Fe(II), Co(II) and Ni(II) have octahedral geometry, while the complex with Cu(II) has a square planar geometry. All the prepared complexes are wholly stable and can keep for months without any significant change. The antibacterial activities of the prepared compounds were evaluated with regard to two bacteria species, gram-negative Proteus and Kelbsiella, by using diffusion agar plates. The inhibition zone diameter around the holes indicated the sensitivity of the bacteria to these compounds, where the Klebsiella bacteria were revealed to be more highly sensitive to these compounds than Proteus bacteria. All synthesized complexes showed more significant effects against Kelbsiella and Protea than the antibiotic (Amikacin).