SYNTHESIS, CHARACTERIZATION AND DNA BINDING ACTIVITY MACROCYCLIC SCHIFF BASE MIXED COMPLEXES BEARING THENIL AND CURCUMIN

The macrocyclic complexes of pharmaceutical importance with transition metals have been synthesized by condensation of condensation of the 1,2-Di(2-thienyl)-1,2-ethanedione (Thenil), ethane-1,2-diamine and curcumin. The structure of the synthesized ligand and complexes was characterized by, elemental analyses, Mass, IR, UV–Vis., measurements. The binding properties of these complexes towards DNA have been investigated using electronic absorption, competitive fluorescence titration, viscosity measurements and circular dichroic analyses. The results obtained indicated that the complexes get bonded with DNA via an intercalation binding mode with an intrinsic binding constant, Kb 6.76 x 104 M-1 , 5.13 x 104 M-1 and 4.18 x 104 M-1 respectively and Kapp of 5.33 x 105 M-1 , 4.04 x 105 M-1 and 3.29 x 105 M-1 . Keywords: Thenil, DNA binding, Curcumin, Intercalation, hydrazine hydrate.