title: Molecular recognition between adenine or 2,6-diaminopurine and copper(II) chelates with N,O2,S-tripodal tetradentate chelators having thioether or disulfide donor groups.
abstract: Five novel ternary copper(II) complexes with the N,O2,S-tripodal tetradentate chelators N,N-bis(carboxymethyl)-S-benzylcysteaminate(2-) ion (BCBC) or N,N,N',N'-tetrakis(carboxymethyl)cystaminate(4-) ion (TCC) and adenine (Hade), 2,6-diaminopurine (Hdap), 2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen) as co-ligand were synthesized and characterized by X-ray diffraction and other physical methods: [Cu2(BCBC)2(μ2-N3,N7-H(N9)ade)(H2O)2]·H2O (1), [Cu2(BCBC)2(μ2-N7,N9-H(N3)dap)(H2O)2]·4H2O (2), [Cu2(μ2-TCC)(H(N9)ade)2(H2O)2]·10H2O (3), [Cu2(μ2-TCC)(bpy)2]·15H2O (4) and [Cu2(μ2-TCC)(phen)2]·14H2O (5). The crystal structure of H4TCC·3H2O was also determined. All ternary Cu(II) complexes have molecular structures. The N-(2-mercaptoethyl)-iminodiacetate moieties of BCBC or TCC ligands play a NO2+S-tripodal tetradentate role, with the S-(thioether or disulfide) atom as the apical/distal donor of the copper(II) center. In 1-3, the iminodiacetate moiety exhibits a mer-NO2 conformation (two nearly coplanar chelate rings) while in 4 and 5 (with bpy or phen as coligand) it displays a fac-NO+O (apical/distal) conformation. We conclude that the formation of the Cu-S(thioether or disulfide) bonds is strongly favored by the N-branched topology of the S-ligands in the reported compounds.
authors.affiliation: Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain. Electronic address: jmgp@ugr.es.
authors.forename: Josefa María
authors.initials: JM
authors.lastname: González-Pérez
authors.affiliation: Laboratorio de Estudios Cristalográficos, IACT, CSIC-University of Granada, Avenida de las Palmeras 4, Armilla 18100 Granada, Spain.
authors.forename: Duane
authors.initials: D
authors.lastname: Choquesillo-Lazarte
authors.affiliation: Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain. Electronic address: alicia.dominguez@chem.uzh.ch.
authors.forename: Alicia
authors.initials: A
authors.lastname: Domínguez-Martín
authors.affiliation: Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain.
authors.forename: Hanan
authors.initials: H
authors.lastname: El Bakkali
authors.affiliation: Department of Organic and Pharmaceutical Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain.
authors.forename: María Eugenia
authors.initials: ME
authors.lastname: García-Rubiño
authors.affiliation: Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Pérez-Toro
authors.affiliation: Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain.
authors.forename: Ester
authors.initials: E
authors.lastname: Vílchez-Rodríguez
authors.affiliation: Department of Inorganic Chemistry, Faculty of Pharmacy, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Castiñeiras
authors.affiliation: Dipartimento di Scienze Chimiche e Geologiche, Università di Cagliari, Cittadela Universitaria, 09042 Monserrato, CA, Italy.
authors.forename: Valeria Marina
authors.initials: VM
authors.lastname: Nurchi
authors.affiliation: Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Niclós-Gutiérrez
mesh_terms: D015075:2-Aminopurine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D000225:Adenine / Q000737:chemistry / Q000378:metabolism*; D002614:Chelating Agents / Q000737:chemistry*; D003300:Copper / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D004220:Disulfides / Q000737:chemistry*; D015394:Molecular Structure; D009584:Nitrogen / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry*; D013455:Sulfur / Q000737:chemistry
chemical_list: D002614:Chelating Agents; D004220:Disulfides; D013440:Sulfides; D015075:2-Aminopurine; C007300:2,6-diaminopurine; D013455:Sulfur; D003300:Copper; D000225:Adenine; D009584:Nitrogen; D010100:Oxygen
keywords: Adenine; Copper(II) complexes; Disulfide; Interligand interactions; Thioether