Metal-promoted hydrolysis of phosphoester bonds: Structural and reactivity studies of water-soluble metal complexes

INOR 173

Marcel Hetu, marcel.hetu@cox.net, Department of Chemistry, San Diego State University, 5500 Campanile Dr, San Diego, CA 92182 and Hong-Chang Liang, hcliang@sciences.sdsu.edu, Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182.
Pyridyl-amine ligands containing water-soluble sulfonate groups with varying tether lengths have been synthesized along with their corresponding Cu(II), Ni(II), and Zn(II) complexes, and several of the complexes have been structurally characterized by X-ray crystallography. To test the abilities of these new complexes towards promoting the hydrolysis phosphoester bonds, each was reacted with bis(4-nitrophenyl)phosphate in buffered water under various pseudo first-order conditions. The complexes were also reacted with Litmus 29 plasmid DNA under both anaerobic and aerobic conditions to test for phosphodiester cleavage of the DNA backbone by comparing the relative amounts of resulting supercoiled, nicked, and linear DNA. The data produced offer interesting insights on the effect of the sulfonate tether length in modulating the reactivities of the complexes.