Synthesis, characterization and biological activity study of some macrocyclic complexes of Co(II), Zn(II) and Cd(II)

Abstract

Macrocyclic chemistry is a growing area of research in inorganic and bioinorganic chemistry in view of its biological significance. The studies of macrocycles have undergone tremendous growth in recent years and their complexation chemistry with a wide variety of metal ions has been extensively studied. Macrocyclic complexes are considered to mimic the synthetic models of metalloporphins and metallocorrins due to their intrinsic structural properties. Macrocyclic complexes have also received special attention because of their mixed soft-hard donor charater and versatile coordination behavior and their pharmacological properties, i.e., toxicity against bacterial growth. The present work is divided into two parts. Firstly, preparation and characterization of some macrocyclic complexes of Co(II), Cd(II) and Zn(II) and secondly, study of their antibacterial activity. Part-I In present work some macrocyclic complex compounds of Co(II), Cd(II) and Zn(II) containing a ligand with tetraoxo tetrahydrazin moiety were prepared by template condensation of malonodihydrazide(C3H8N4O2 ) with different aldehydes. The macrocyclic complexes [Cd(C8N8O4H16)(ClO4)2], [Cd(C10N8O4H20)(ClO4)2], [Cd(C24N8O4H28)(ClO4)2] and [Cd(C14N8O4H24)(ClO4)2] (1-4) were prepared by the reaction of malonodihydrazide, (C3H8N4O2) with cadmium(II) perchlorate hexahydrate in presence of formaldehyde, acetaldehyde, cinnamaldehyde and crotonaldehyde respectively in 2:1:2 molar ratio. The macrocyclic complexes [Co(C8N8O4H16)(ClO4)2] and [Co(C24N8O4H28)(ClO4)2] (5-6) were prepared by the reaction of malonodihydrazide(C3H8N4O2), with Co(II) perchlorate hexahydrate in the presence of formaldehyde and cinnamaldehyde respectively in 2:1:2 molar ratio. The macrocyclic complexes (1-6) are characterized by elemental analysis, UV-visible and IR spectral analysis, magnetic moment and conductance measurements and some other physical properties.