title: Association patterns of platinated purine nucleobases in metal-modified pairs and triples.
abstract: Blocking of Watson-Crick or Hoogsteen edges in purine nucleobases by a metal entity precludes involvement of these sites in interbase hydrogen bonding, thereby leaving the respective other edge or the sugar edge as potential H bonding sites. In mixed guanine, adenine complexes of trans-a2PtII (a = NH3 or CH3NH2) of composition trans-[(NH3)2Pt(9-EtA-N1)(9-MeGH-N7)](NO3)2 (1a), trans-[(NH3)2Pt(9-EtA-N1)(9-MeGH-N7)](ClO4)2 (1b), and trans,trans-[(CH3NH2)2(9-MeGH-N7)Pt(N1-9-MeA-N7)Pt(9-MeGH-N7)(CH3NH2)2](ClO4)4*2H2O (2) (with 9-EtA = 9-ethyladenine, 9-MeA= 9-methyladenine, 9-MeGH = 9-methylguanine), this aspect is studied. Thus, in 1b pairing of two adenine ligands via Hoogsteen edges and in 2 pairing of two guanine bases via sugar edges is realized. These situations are compared with those found in a series of related complexes.
authors.affiliation: Fachbereich Chemie, Universität Dortmund, 44221 Dortmund, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Roitzsch
authors.forename: Irene B
authors.initials: IB
authors.lastname: Rother
authors.forename: Michael
authors.initials: M
authors.lastname: Willermann
authors.forename: Andrea
authors.initials: A
authors.lastname: Erxleben
authors.forename: Burkhard
authors.initials: B
authors.lastname: Costisella
authors.forename: Bernhard
authors.initials: B
authors.lastname: Lippert
mesh_terms: D020029:Base Pairing; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D018360:Crystallography, X-Ray; D004578:Electron Spin Resonance Spectroscopy; D006147:Guanine / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D009944:Organoplatinum Compounds / Q000737:chemistry*; D011687:Purines / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D009944:Organoplatinum Compounds; D011687:Purines; D006147:Guanine