Syntheses, Crystal Structures and DNA-Binding of Two Copper(II) Complexes Constructed by 4-Methyl-1,2,3-thiadiazol-5-carboxylic Acid

Two copper complexes [Cu(MTC)(2)(H2O)(2)](n) (1) and [Cu-2(MTC)(2)(Phen)(2)(H2O)(4)](MTC)(2) (2) were synthesized by 4-methyl-1,2,3-thiadiazol-5-carboxylic acid(HMTC, C4H4N2O2S) and 1,10-phenanthroline(Phen), and structurally characterized by elemental analysis, IR spectra, TG, PXRD and single crystal X-ray diffraction method. The single crystal X-ray diffraction reveals that the complex 1 formed a 1D chain coordination ploymer and crystallized in monoclinic with space group P2(1)/c. Central Cu2+ was five-coordinated forming a distorted pentahedron coordination geometry. The complex 2 was a binuclear structure, which was bridged by two oxygen atoms from two coordinated water, and crystallized in triclinic with space group P (1) over bar. Central Cu2+ was six-coordinated forming a distorted octahedron coordination geometry. In addition, the interaction of complexes and ligand with DNA were also studied by ethidium bromide fluorescence probe. The interaction of complex 2 with DNA was stronger than complex 1. CCDC: 825716, 1; 1435439, 2.