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Copper (II) complex of formulation [Cu-Phen-Tyr](HO)](ClO) (Phen = 1,10-phenanthroline, l-Tyr = l-tyrosine), has been prepared, and their induced DNA oxidative cleavage activity studied. The complex binds to DNA by intercalation, as deduced from the absorption and fluorescence spectral data. Scatchard plots constructed from the absorption titration data gave binding constant 2.44 × 10 M of base pairs. Extensive hypochromism, broadening, and red shifts in the absorption spectra were observed. Upon binding to DNA, the fluorescence from the DNA-ethidium bromide system was efficiently quenched by the copper (II) complex. Stern-Volmer quenching constant 0.61 × 10 M obtained from the linear quenching plots. [Cu-Phen-Tyr] complex efficiently cleave the supercoiled DNA to its nicked circular form with gallic acid as biological reductant at appropriate complex concentration. The gallic acid as reductant could observably improve copper (II) complex to DNA damage. The pseudo-Michaelis-Menten kinetic parameters ( k, K) were calculated to be 1.32 h and 5.46 × 10 M for [Cu-Phen-Tyr] complex. Mechanistic studies reveal the involvement of superoxide anions and hydroxyl radical (HO) as the reactive species under an aerobic medium. [ABSTRACT FROM AUTHOR]

Copper(II) complexes of diclofenac with interesting anti-inflammatory profiles have been prepared and studied by infrared and electronic spectroscopy. In the solid state and in polar and coordinating solvents, all the complexes are solvated binuclear carboxylato-bridged complexes, [Cu(L)2(S)]2, where L is monodeprotonated diclofenac and S is the axially bonded solvent. The effect of the copper(II) complexes on the in vitro DNA strand breakeage was studied by agarose gel electrophoresis. Relaxation or double stranded scissions of pDNA were observed leading to the formation of linear pDNA. Treatment of pDNA with high concentrations of these compounds caused a disappearance of pDNA. For the parent drug, sodium diclofenac, no effect on the pDNA was observed. This study presents some indications that the binuclear copper(II) complexes, [Cu(L)2(S)]2, could have some relevance in the treatment of tumor cell lines. [ABSTRACT FROM AUTHOR]