title: Blue copper protein analogue: synthesis and characterization of copper complexes of the N2S2 macrocycle 1,8-dithia-4,11-diazacyclotetradecane.
abstract: To improve understanding of copper at the active site of Type 1 copper proteins, Cu(I) and Cu(II) complexes of 1,8-dithia-4,11-diazacyclotetradecane, shown in , have been successfully isolated and structurally characterized by X-ray crystallography. In these compounds, both Cu(I) and Cu(II) are centered in the plane of the macrocycle containing two sulphur and two nitrogen heteroatoms comprising the distorted tetrahedral/square planar coordination geometry. The UV/VIS spectra, electrochemistry and EPR properties have been obtained for the Cu(II) complex 2. Three absorption bands at 295 nm, 354 nm, and 545 nm are observed in aqueous solution at a pH of 5. These bands have been assigned to the N → Cu(II) and S → Cu(II) charge transfer bands and the d-d transitions respectively. The Cu(I/II) redox midpoint potential of complex 2 in CH3CN is +403 mV versus NHE.
authors.affiliation: Department of Chemistry, Indiana University Northwest, Gary, IN 46408, USA. tialwalk@iun.edu.
authors.forename: Tia L
authors.initials: TL
authors.lastname: Walker
authors.affiliation: Department of Chemistry, Brock University, St. Catharines, ON L2S 3A1, Canada.
authors.forename: Sam
authors.initials: S
authors.lastname: Mula
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44335, USA.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Malasi
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44335, USA.
authors.forename: James T
authors.initials: JT
authors.lastname: Engle
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44335, USA.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ziegler
authors.affiliation: Department of Chemistry, Brock University, St. Catharines, ON L2S 3A1, Canada.
authors.forename: Art
authors.initials: A
authors.lastname: van der Est
authors.affiliation: Department of Chemistry, Hiram College, Hiram, OH 44234, USA.
authors.forename: Jody
authors.initials: J
authors.lastname: Modarelli
authors.affiliation: Department of Chemistry, The University of Akron, Akron, OH 44335, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Taschner
mesh_terms: D020134:Catalytic Domain; D056831:Coordination Complexes / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006573:Heterocyclic Compounds, 1-Ring / Q000737:chemistry*; D008667:Metalloproteins / Q000737:chemistry*; D008958:Models, Molecular
chemical_list: D056831:Coordination Complexes; D006573:Heterocyclic Compounds, 1-Ring; D008667:Metalloproteins; D003300:Copper