Carboxylic acid functionalized cobalt(III) cyclen complexes for catalytic hydrolysis of phosphodiester bonds

摘要

4-(l,4,7,10-Tetraazacyclotetradec-l-yl)methylbenzoic acid (cycmba,1) has been synthesized,as a step towards the eventual development of sequence-specific hydrolytic complexes.A cobalt(III) complex of 1,[Co(cycmba)Cl_2]Cl.1.5H_2O (2.1.5H_2O) was found to be active against both an activated phosphodiester compound,bis(nitrophenyl)-phosphate (BNPP),and supercoiled DNA.The presence of the benzoate group depresses the rate of hydrolysis of the ligand-Co(III) system at neutral pH,as confirmed by the kinetics results of a methyl ester analog.The ability of (2-1.5H_2O) to bind to solid substrates and remain active was also demonstrated by attachment of the molecule to agarose beads.