title: DNA binding and nucleolytic properties of Cu(ii) complexes of salicylaldehyde semicarbazones.
abstract: The copper(ii) complexes of two salicylaldehyde semicarbazones, HOC(6)H(4)CH[double bond, length as m-dash]N-NHCONR(2) [H(2)Bnz(2) (R = CH(2)Ph) and H(2)Bu(2) (R = Bu)], were evaluated for their DNA binding and cleavage properties by spectrophotometric DNA titration, ethidium bromide displacement assay and electrophoretic mobility shift assay. Results showed that the Cu(ii) complexes can bind to DNA via a partial intercalation mode with binding constants of 1.1 × 10(4) and 9.5 × 10(3) M(-1) for [Cu(HBnz(2))Cl] and [Cu(HBu(2))Cl], respectively. These complexes also cleave DNA in the presence of ascorbic acid, most likely through hydroxyl radicals that are generated via the reduction of a Cu(ii) to a Cu(i) species. The complexes show similar DNA cleavage activity, which is reflected in the similarity of their frontier molecular orbital energies calculated by density functional theory. These results are discussed in relation to the anticancer properties of the complexes.
authors: Natural Sciences & Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616, Republic of Singapore.
authors: Wan Yen
authors: WY
authors: Lee
authors: Yaw Kai
authors: YK
authors: Yan
authors: Peter Peng Foo
authors: PP
authors: Lee
authors: Shiow Jin
authors: SJ
authors: Tan
authors: Kok Hwa
authors: KH
authors: Lim
mesh_terms: D000447:Aldehydes / Q000737:chemistry* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000494:pharmacology; D002413:Cations, Divalent / Q000737:chemistry / Q000494:pharmacology; D056831:Coordination Complexes / Q000737:chemistry* / Q000494:pharmacology; D003300:Copper / Q000737:chemistry* / Q000494:pharmacology; D004247:DNA / Q000737:chemistry*; D053837:DNA Cleavage; D004278:DNA, Superhelical / Q000737:chemistry / Q000235:genetics; D003851:Deoxyribonucleases / Q000737:chemistry / Q000378:metabolism; D004996:Ethidium / Q000494:pharmacology; D008958:Models, Molecular; D010957:Plasmids / Q000737:chemistry / Q000235:genetics; D012664:Semicarbazones / Q000737:chemistry* / Q000494:pharmacology; D013050:Spectrometry, Fluorescence
chemical_list: D000447:Aldehydes; D002413:Cations, Divalent; D056831:Coordination Complexes; D004278:DNA, Superhelical; D012664:Semicarbazones; C013243:salicylaldehyde; D003300:Copper; D004247:DNA; D003851:Deoxyribonucleases; D004996:Ethidium; D001205:Ascorbic Acid