title: 1,8-Naphthyridin-2,7-(1,8H)-dione is an effective mimic of protonated cytosine in peptide nucleic acid triplex recognition systems.
abstract: A novel bicyclic mimic of protonated cytosine [1,8-naphthyridin-2,7-(1,8H)-dione, (K)] for Hoogsteen type triplex recognition of guanine has been designed for incorporation into peptide nucleic acids. Bis-PNA clamps with the K base incorporated in the Hoogsteen strand showed a significant stabilization of the triplexes at pH 7 as compared to similar triplexes with PNA oligomers containing either cytosine (6.7 degrees C per unit) or pseudoisocytosine (1.5 degrees C per unit). Cooperative stabilization was observed when the K units were placed in adjacent positions ( approximately 3 degrees C per unit).
authors.affiliation: Center for Biomolecular Recognition, Department of Medical Biochemistry and Genetics, The Panum Institute, University of Copenhagen, Blegdamsvej 3, DK-2200 N, Copenhagen, Denmark.
authors.forename: Caspar
authors.initials: C
authors.lastname: Christensen
authors.forename: Anne  B
authors.initials: A
authors.lastname: Eldrup
authors.forename: Gerald
authors.initials: G
authors.lastname: Haaima
authors.forename: Peter E
authors.initials: PE
authors.lastname: Nielsen
mesh_terms: D001643:Bridged Bicyclo Compounds / Q000138:chemical synthesis* / Q000494:pharmacology*; D003596:Cytosine / Q000737:chemistry*; D004247:DNA / Q000737:chemistry / Q000187:drug effects; D004355:Drug Stability; D006147:Guanine / Q000737:chemistry; D006358:Hot Temperature; D006860:Hydrogen Bonding; D007202:Indicators and Reagents; D018716:Molecular Mimicry; D009287:Naphthyridines / Q000138:chemical synthesis* / Q000494:pharmacology*; D020135:Peptide Nucleic Acids / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: C471980:1,8-naphthyridin-2,7-(1,8H)-dione; D001643:Bridged Bicyclo Compounds; D007202:Indicators and Reagents; D009287:Naphthyridines; D020135:Peptide Nucleic Acids; D006147:Guanine; D003596:Cytosine; D004247:DNA