One-dimensional cobalt(II) and three-dimensional manganese(II) coordination polymers with pyrazine-2-carboxamide: X-ray studies, spectroscopic characterization and biological studies

چکیده مقاله

Two novel coordination polymers based on pyrazine-2-carboxamide (PzCA), {[Co(μ-PzCA)(PzCA)(H₂O)](NO₃)₂}_n (Co^PzCA) and [Mn(μ-PzCA)(μ-NO₃)(NO₃)]_n (Mn^PzCA), were synthesized and characterized using single crystal X-ray diffraction method, FT-IR, and UV-Vis spectroscopy. Co^PzCA crystallizes in a monoclinic system and forms a one-dimensional coordination polymer, in which water molecules are arranged in a star-like configuration, with additional non-covalent interactions contributing to the overall crystal packing. Mn^PzCA adopts an orthorhombic structure, also forming a unique three-dimensional coordination polymer. In both compounds, the metal centers exhibit distorted octahedral geometries. The bioactivity assays revealed that Mn^PzCA demonstrated significant antioxidant activity, efficiently scavenging free radicals in vitro, while Co^PzCA exhibited the most pronounced antibacterial activity, particularly against Staphylococcus aureus (Gram-positive), whereas the free ligand and Mn^PzCA showed limited or no inhibition. © 2025 Elsevier B.V.