Synthetic, Structural and Biological Studies on Divalent Tin Complexes of Sixteen to Twenty-Four Membered Tetraaza Macrocycles

Abstract

A new series of 16- to 24-membered macrocycles of tin(II) containing tetraaza groups has been prepared by the template condensation reaction of glutaric acid and phthalic acid with 1,2-phenylenediamine, 2,6-diaminopyridine, and diethylenetriamine in 1:2:2 molar ratios. The reaction products were characterized by elemental analyses, molecular weight determinations, infrared, 1 H NMR, 119 Sn NMR, and mass spectral studies. X-ray powder diffraction spectrum of one representative compound also has been reported. The hexacoordinated state for tin has been confirmed by spectral studies. An octahedral geometry for these complexes has been proposed as the binding sites are the nitrogen atoms of the macrocycle. The formulation of the complexes as [Sn(N 4 MaC n )Cl 2 ] (where N 4 MaCn represent the ligand molecule and n = 1 to 6 has been established on the basis of the chemical composition. All of the complexes are monomeric. The ligands and their complexes also have been screened for their antimicrobial activities and the results are discussed.