title: Synthesis and DNA interaction of ethylenediamine platinum(II) complexes linked to DNA intercalants.
abstract: A series of ethylenediamine platinum(II) complexes connected through semi-rigid chains of 1,2-bis(4-pyridyl)ethane to DNA intercalating subunits (naphthalene, anthracene or phenazine) has been synthesized, and their interactions with calf thymus (CT) DNA have been evaluated by viscometric titrations and equilibrium dialysis experiments. The parent ligands that contain anthracene or phenazine chromophores showed a monointercalative mode of DNA interaction (especially the anthracene derivative), with apparent association constants in the order of 10(4) M(-1). The corresponding platinum(II) complexes bind CT DNA through bisintercalation, as established by the significant increase of DNA contour length inferred from viscosity measurements, and the association constants are in the order of 10(5) M(-1). The naphthalene derivatives, however, exhibit a mixed mode of interaction, which suggests a partial contribution of both intercalation and groove binding for the ligand, and monointercalation in the case of the platinum(II) complex. Competition dialysis experiments carried out on the intercalative compounds have revealed a moderate selectivity towards GC DNA sequences for the derivatives containing the anthracene chromophore.
authors.affiliation: Departamento de Química Orgánica, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain.
authors.forename: Katerina
authors.initials: K
authors.lastname: Duskova
authors.forename: Sara
authors.initials: S
authors.lastname: Sierra
authors.forename: María-José
authors.initials: MJ
authors.lastname: Fernández
authors.forename: Lourdes
authors.initials: L
authors.lastname: Gude
authors.forename: Antonio
authors.initials: A
authors.lastname: Lorente
mesh_terms: D000818:Animals; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D005029:Ethylenediamines / Q000138:chemical synthesis* / Q000737:chemistry*; D007364:Intercalating Agents / Q000138:chemical synthesis* / Q000737:chemistry*; D007700:Kinetics; D009944:Organoplatinum Compounds / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D005029:Ethylenediamines; D007364:Intercalating Agents; D009944:Organoplatinum Compounds; C031234:ethylenediamine; D004247:DNA; C427203:calf thymus DNA