Abstract

Brine shrimp lethality of a new series of 16 to 26-membered macrocycles of iron(II) containing tetraaza groups and prepared by the template condensation reaction of diacarboxylic acids (malonic, succinic, glutaric or adipic) with 2,6-diaminopyridine and diethylenetriamine in 1:2:2 molar ratios have been studied. Structures and bonding of the macrocyclic complexes have been proposed based on elemental analyses, IR, electronic, X-ray and mass spectral studies. An octahedral geometry for these complexes has been proposed as the binding sites are the nitrogen atoms of the macrocycles. The formation of the complexes as [Fe(Ln)Cl2] has been established on the basis of the chemical composition. The complexes have also been screened against several microbes.