Building-up novel coordination polymer with magnesium porphyrin: Synthesis, molecular structure, photophysical properties and spectroscopic characterization. Potential application as antibacterial agent

•Synthesis of a new Mg(II) porphyrin polymer with the 4,4'-dipyridine ligand: (I).•UV-visible, fluorescence, IR and 1H NMR spectroscopic characterization of (I).•Cyclic voltammetry investigation of (I).•X-ray molecular structure of (I) showing C–H…π intermolecular interactions.•exhibits promising antibacterial activity for Gram-(+) and (−) bacteria.