Syntheses, Characterization and Crystal Structures of Schiff Base Zinc(II) Complexes with Antibacterial Activity

Two polynuclear zinc(II) complexes, [Zn2(L1)2(OH2)2] (1) and [ZnL2(μ1,1-N3)]n (2), where L1 is the dianionic form of N,N'-bis(3,5-difluoro-2-hydroxybenzylidene)-1,3-diaminopropane, and L2 is the monoanionic form of 2-[(2-dimethylaminoethylimino)methyl]-4,6-difluorophenol, have been prepared and structurally characterized by elemental analyses, IR and UV-Vis spectroscopy, as well as single-crystal X-ray diffraction. In complex 1, the Zn atom is in octahedral coordination, with the donor atoms of the Schiff base ligands L1 and one water O atom. In complex 2, the Zn atom is in trigonal-bipyramidal coordination, with the three donor atoms of the Schiff base ligand L2 and two azido N atoms. The complexes have strong antibacterial activity against B. subtilis and S. aureus.