Synthesis, Characterization, Thermal Behavior, and DNA-Cleaving Studies of Cyano-Bridged Nickel(II)Copper(II) Complexes of 4-(Pyridin-2-ylazenyl)resorcinol

• Published in: Chemistry & biodiversity 2011-10, Vol.8 (10), p.1871-1879
• Main Authors: Karipcin, Fatma, Özmen, İsmail, Cülü, Burcin, Çelikoğlu, Umut
• Format: Article
• Language: English
• Subjects: 4-(pyridin-2-ylazenyl); Azo dyes; Copper - chemistry; Copper complexes; Cyano bridges; Differential Thermal Analysis; DNA; DNA - chemistry; Electrophoresis, Agar Gel; Hydrogen Peroxide - chemistry; Ligands; Molecular Structure; Nickel - chemistry; Nickel complexes; Organometallic Compounds - chemical synthesis; Organometallic Compounds - chemistry; Resorcinol; Resorcinol, 4‐(pyridin‐2‐ylazenyl); Resorcinols - chemistry; Spectrophotometry, Infrared
• ISSN: 1612-1872; 1612-1880
• DOI: 10.1002/cbdv.201000209

We present here the syntheses of a mononuclear CuII complex and two polynuclear CuIINiII complexes of the azenyl ligand, 4‐(pyridin‐2‐ylazenyl)resorcinol (HL; 1). The reaction of HL (1) and copper(II) perchlorate with KCN gave a mononuclear complex [CuL(CN)] (4). Using 4, one pentanuclear complex, [{CuL(NC)}4Ni](ClO4)2 (5) and one trinuclear complex, [{CuL(CN)}2NiL]ClO4 (6), were prepared and characterized by elemental analyses, magnetic susceptibility, molar conductance, IR, and thermal analysis. Stoichiometric and spectral results of the mononuclear CuII complex indicated that the metal/ligand/CN ratio was 1 : 1 : 1, and the ligand behaved as a tridentate ligand forming neutral metal chelates through the pyridinyl and azenyl N‐, and resorcinol O‐atom. The interaction between the compounds (the ligand 1, its NiII and CuII complexes without CN, i.e., 2 and 3, and its complexes with CN, 4–6) and DNA has also been investigated by agarose gel electrophoresis. The pentanuclear Cu4Ni complex (5) with H2O2 as a co‐oxidant exhibited the strongest DNA‐cleaving activity.