SYNTHESIS OF A NEW COPPER COMPLEX OF A MACROCYCLIC COMPOUND CONSISTING OF 1,10-PHENANTHROLINE, AND ITS DNA-BINDING AND CLEAVING ACTIVITY

A copper complex of a macrocylcic compound consisting of two 1,10-phen anthroline molecules bridge two sulfur atoms, [Cu(smc)], was synthesiz ed. The interaction of [Cu(smc)] with DNA was examined by UV-vis absor ption spectroscopy, circular dichroism spectroscopy, and viscometry. T he binding constant of [Cu(I)(smc)] with DNA is 4.2 x 10(4) M-1, which is almost identical with that of bis(1,10-phenanthroline)copper, [Cu( I)(phen)2]. A viscosity measurement indicates that [Cu(I)(smc)] binds to DNA by an intercalative mode. [Cu(smc)] cleaves DNA in the presence of a reducing agent under an aerobic condition. In this process .OH p lays an important role.