title: DNA interaction studies of a copper (II) complex containing an antiviral drug, valacyclovir: the effect of metal center on the mode of binding.
abstract: The water-soluble complex, [Cu(Val)(2)(NO(3))(2)]; in which Val = valacyclovir, an antiviral drug, has been synthesized and characterized by elemental analysis, furier transfer-infrared, hydrogen nuclear magnetic resonance (H NMR), and UV-Vis techniques. The binding of this Cu (II) complex to calf thymus DNA was investigated using fluorimetry, spectrophotometry, circular dichroism, and viscosimetry. In fluorimetric studies, the enthalpy and entropy of the reaction between the complex and calf-thymus DNA (CT-DNA) showed that the reaction is endothermic (ΔH = 208.22 kJ mol(-1); ΔS = 851.35 J mol(-1)K(-1)). The complex showed the absorption hyperchromism in its ultra violet-visible (UV-Vis) spectrum with DNA. The calculated binding constant, K(b), obtained from UV-Vis absorption studies was 2 × 10(5) M(-1). Moreover, the complex induced detectable changes in the circular dichroism spectrum of CT-DNA, as well as changes in its viscosity. The results suggest that this copper (II) complex interacts with CT-DNA via a groove-binding mode.
authors.affiliation: Department of Chemistry, Faculty of Science, Razi University, Kermanshah, Iran. nahidshahabadi@yahoo.com
authors.forename: Nahid
authors.initials: N
authors.lastname: Shahabadi
authors.forename: Parvin
authors.initials: P
authors.lastname: Fatahi
mesh_terms: D000212:Acyclovir / Q000031:analogs & derivatives* / Q000737:chemistry; D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry*; D001665:Binding Sites; D002417:Cattle; D003300:Copper / Q000737:chemistry*; D004247:DNA / Q000378:metabolism*; D009942:Organometallic Compounds / Q000737:chemistry* / Q000378:metabolism*; D013057:Spectrum Analysis; D013329:Structure-Activity Relationship; D000077483:Valacyclovir; D014633:Valine / Q000031:analogs & derivatives* / Q000737:chemistry; D014783:Viscosity
chemical_list: D000998:Antiviral Agents; D009942:Organometallic Compounds; D003300:Copper; D004247:DNA; D014633:Valine; D000077483:Valacyclovir; D000212:Acyclovir