Related Experiment Video
Updated: Jul 16, 2026

Nucleoside Triphosphates - From Synthesis to Biochemical Characterization
Published on: April 3, 2014
Unique ligand-based oxidative DNA cleavage by zinc(II) complexes of hpyramol and hpyrimol
Palanisamy Uma Maheswari1, Sharief Barends, Seniz Ozalp-Yaman
1Gorlaeus Laboratories, Leiden University, 2300 RA Leiden, The Netherlands.
Abstract:
The zinc(II) complexes reported here have been synthesised from the ligand 4-methyl-2-N-(2-pyridylmethyl)aminophenol (Hpyramol) with chloride or acetate counterions. All the five complexes have been structurally characterised, and the crystal structures reveal that the ligand Hpyramol gradually undergoes an oxidative dehydrogenation to form the ligand 4-methyl-2-N-(2-pyridylmethylene)aminophenol (Hpyrimol), upon coordination to Zn(II). All the five complexes cleave the phiX174 phage DNA oxidatively and the complexes with fully dehydrogenated pyrimol ligands were found to be more efficient than the complexes with non-dehydrogenated Hpyramol ligands. The DNA cleavage is suggested to be ligand-based, whereas the pure ligands alone do not cleave DNA. The DNA cleavage is strongly suggested to be oxidative, possibly due to the involvement of a non-diffusible phenoxyl radical mechanism. The enzymatic religation experiments and DNA cleavage in the presence of different radical scavengers further support the oxidative DNA cleavage by the zinc(II) complexes.
Related Concept Videos
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Radical Formation: Homolysis
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Maxam-Gilbert Sequencing
Challenges of the Maxam-Gilbert Method
The...
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids

