Synthesis, spectroscopic characterization and biological studies of mixed ligand complexes of metal ions

Abstract

The chemistry of flexible multidentate chelating ligands and their complexes is main stream of research for coordination and bio-inorganic chemists. The functionalized polycarboxylic acids like oxydiacetic acid (H2oda), iminodiacetic acid (H2imda), nitrilotriacetic acid (H3nta) and simple dicarboxylic acids like adipic acid (H2ada) are among the potential flexible multidendtate chelating agents, which are capable to produce different kinds of polynuclear complexes. These multifunctional carboxylic acids exhibit a diversified coordination mode and provide an effective hydrogen bonding interaction with other protic group satisfying one of the foremost conditions for the generation of supramolecular architectures. Recent investigations on metallo-proteins have revealed that the carboxylate group plays an important role for structural holding and proton transfer via hydrogen bonding interactions in proteins. Carboxylate bridged complexes have been the most attractive synthetic target in view of the fact that the carboxylate bridgings are effective in providing polynuclear structural motifs as observed in the various O2-metabolic non-heme Fe- and Mn-proteins. Spectroscopic studies on interaction of iron clusters with calf thymus DNA have also been used to evaluate effectivity of the binding to DNA. 1D, 2D and 3D coordination polymeric metal- rganic frameworks (MOFs) are effectively generated via extensive carboxylate bridging in metal complexes containing functionalized polycarboxylate moieties. Several monometallic as well as bimetallic complexes incorporating such donor ligands have been studied for their in vitro antitumor activities. These complexes have also been used as possible antimicrobial agents. The present studies have been discussed in five different headings excluding a general introduction (Chapter I) of the subject as follows:Chapter I deals with the general introduction and review of the chemistry of simple or functionalized polycarboxylic acid and their binary and ternary complexes of metal ions.