Synthesis, Structure and Antibacterial Activity of a Neutral Tin(II) Iodide Complex with 1,2-bis[(4-Methoxyphenyl)imino]acenaphthene

Abstract

The reaction of tin(II) iodide with 1,2-bis[(4-methoxyphenyl)imino]acenaphthene (4-MeO-BIAN) in anhydrous tetrahydrofuran afforded the neutral complex [(4-MeO-BIAN)SnI(μ-I)]2 (1). A single-phase sample of 1 was isolated and characterized by powder X-ray diffraction and IR spectroscopy. The crystal structure of 1 was determined by single-crystal X-ray diffraction: a centrosymmetric dimeric structure with an Sn2I2 core formed by two μ2-bridging iodide ligands; each Sn(II) center is additionally coordinated by a bidentate 4-MeO-BIAN ligand and one terminal iodide ligand. The antibacterial activity of 1 was evaluated in vitro against clinically significant Gram-positive (Staphylococcus aureus, Enterococcus faecium, Enterococcus faecalis) and Gram-negative (Escherichia coli) bacteria. Complex 1 exhibited moderate antibacterial activity against all tested strains, with MIC values of 40–312.5 µg/mL and MBC values of 62.5–312.5 µg/mL. The lowest MIC values, close to those of meropenem (MIC = 32 µg/mL), were obtained against Staphylococcus aureus (MIC = 40 µg/mL).