title: Mn(II) complexes with sulfonamides as ligands. DNA interaction studies and nuclease activity.
abstract: Sulfonamides derived from 8-aminoquinoline react with Mn(II) and Mn(III) salts to form Mn(II) complexes; the Mn(III) species are reduced to the divalent state in the presence of 1,10 phenanthroline and bipyridine. Their molecular structure, determined by single crystal X-ray diffraction, show that all the complexes present a distorted octahedral geometry, in which the deprotonated sulfonamide acts as a bidentate ligand. UV-visible spectroscopy and changes in the melting temperature (Tm) of calf thymus DNA show a strong interaction of these complexes with DNA. The significant hypochromicity of the charge transfer transition at 370 nm without an appreciable change in wavelength and the minor changes in the relative viscosity of calf thymus DNA have been attributed to an interaction between the surface of DNA and the complexes. [Mn(qbsa)(2)(MeOH)(2)], [Mn(qbsa)(2)(phen)], [Mn(qtsa)(2)(H(2)O)(2)] and [Mn(qtsa)(2)(phen)] (where qbsa=N-quinolin-8-yl-bencenesulfonamide, qtsa=N-quinolin-8-yl-p-toluenesulfonamide and qnsa=N-quinolin-8-yl-naftalenesulfonamide) exhibit a prominent nuclease activity and the mechanism of DNA cleavage is investigated.
authors.affiliation: Departamento de Química Inorgánica, Facultad de Farmacia, Universidad de Salamanca, Campus Unamuno, 37007 Salamanca, Spain. bmacias@usal.es
authors.forename: Benigno
authors.initials: B
authors.lastname: Macías
authors.forename: María V
authors.initials: MV
authors.lastname: Villa
authors.forename: Rebeca
authors.initials: R
authors.lastname: Lapresa
authors.forename: Gloria
authors.initials: G
authors.lastname: Alzuet
authors.forename: Javier
authors.initials: J
authors.lastname: Hernández-Gil
authors.forename: Francisca
authors.initials: F
authors.lastname: Sanz
mesh_terms: D000818:Animals; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D003851:Deoxyribonucleases / Q000138:chemical synthesis* / Q000737:chemistry*; D008345:Manganese / Q000737:chemistry*; D015394:Molecular Structure; D010957:Plasmids / Q000737:chemistry*; D013449:Sulfonamides / Q000737:chemistry*
chemical_list: D013449:Sulfonamides; D008345:Manganese; D004247:DNA; D003851:Deoxyribonucleases