Abstract: Deoxyribonucleic acid (DNA) is a molecule carrying genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. Hydrolysis of phosphodiester bond of DNA (DNA cleavage) is of critical importance at several stages in cell cycle and design of artificial metallonucleases.DNA binding is important for nuclease to exhibit DNA cleavage activity. Hence an attempt is made in this article to compare the DNA binding abilities of few amino acid based schiff base complexes reported earlier. Ternary Cu(II) - schiff base - heterocyclic base complexes [Cu(II)(saltrp)(phen)] (1), [Cu(II)(saltrp)(bipy)] (2), [Cu(II)(saltyr)(phen)] (3) and [Cu(II)(saltyr)(bipy)] (4) (where saltrp/saltyr = Schiff base derived from salicylaldehyde (sal) and amino acids – tryptophan (trp) or tyrosine (tyr); phen = 1,10 phenanthroline and bipy= 2,2’ bipyridine) were synthesized and characterized. Complexes (1-4) exhibited square pyramidal geometry (CuN3O2) where Schiff base (saltrp and saltyr) and heterocyclic base act as ONO and as NN donor ligands respectively. Calf thymus (CT) DNA ability of complexes (1-4) studied by various techniques revealed that the complexes bind through intercalative mode and show good binding ability. The DNA binding ability of the complexes follow the order 1>2>3>4. Phenanthroline complexes (1,3) binds DNA more effectively as compared to their corresponding bipyridine (2,4) complexes due to the presence of extended aromatic phenyl ring which might be involved in an additional stacking interaction with DNA bases.

Keywords: Schiff base, Copper complexes, DNA binding, Absorption & Fluorescence Spectroscopy.

| DOI: 10.17148/IARJSET.2021.85124