title: Synthesis and photophysical evaluation of a pyridinium 4-amino-1,8-naphthalimide derivative that upon intercalation displays preference for AT-rich double-stranded DNA.
abstract: The synthesis, characterisation and solid state crystal structure of a cationic 4-amino-1,8-naphthalimide derivative (1) are described. The photophysical properties of 1 are shown to vary with the solvent polarity and H-bonding ability. The fluorescence of 1 is enhanced and blue-shifted in its 1:1 complex with 5'-adenosine-monophosphate while it is partially quenched and red-shifted in its complex with 5'-guanosine-monophosphate. Linear and circular dichroism measurements show that 1 binds to double-stranded DNA by intercalation. Comparative UV-visible and fluorescence studies with double stranded synthetic polynucleotides poly(dA-dT)(2) and poly(dG-dC)(2) show that 1 binds much more strongly to the AT polymer; 1 also has a strong preference for A-T rich sequences in natural DNA. Thermal denaturation measurements also reveal a much greater stabilisation of the double-stranded poly(dA-dT)(2) than of natural DNA.
authors.affiliation: School of Chemistry, Centre of Synthesis and Chemical Biology, University of Dublin, Trinity College Dublin, Dublin2, Ireland.
authors.forename: Swagata
authors.initials: S
authors.lastname: Banerjee
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Kitchen
authors.forename: Thorfinnur
authors.initials: T
authors.lastname: Gunnlaugsson
authors.forename: John M
authors.initials: JM
authors.lastname: Kelly
mesh_terms: D000249:Adenosine Monophosphate / Q000737:chemistry; D001482:Base Composition; D001665:Binding Sites; D002942:Circular Dichroism; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D006157:Guanosine Monophosphate / Q000737:chemistry; D006860:Hydrogen Bonding; D007364:Intercalating Agents / Q000138:chemical synthesis*; D053644:Naphthalimides / Q000138:chemical synthesis*; D055668:Photochemical Processes; D011067:Poly dA-dT / Q000737:chemistry; D011089:Polydeoxyribonucleotides / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D007364:Intercalating Agents; D053644:Naphthalimides; D011089:Polydeoxyribonucleotides; D012997:Solvents; D011067:Poly dA-dT; C019530:poly(dC-dG); D000249:Adenosine Monophosphate; D006157:Guanosine Monophosphate; D004247:DNA