title: Double-headed nucleotides introducing thymine nucleobases in the major groove of nucleic acid duplexes.
abstract: Four different double-headed nucleosides each combining two thymine nucleobases with different linkers were synthesised. The 5-position of 2'-deoxyuridine was connected to the N1-position of a thymine through either m- or p-disubstituted phenyl or phenylacetylene linkers by the use of Suzuki or Sonogashira couplings. When introduced into oligonucleotides, the thermal stability of dsDNA and DNA : RNA duplexes were determined and structural information was obtained from CD- and fluorescence spectroscopy. Also the recognition of abasic sites was studied. In general, the more stable duplexes were obtained with m- rather than p-substitution and with phenylacetylene rather than phenyl linkers.
authors.affiliation: Nucleic Acid Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark. pouln@sdu.dk.
authors.forename: Michael
authors.initials: M
authors.lastname: Dalager
authors.forename: Nicolai K
authors.initials: NK
authors.lastname: Andersen
authors.forename: Pawan
authors.initials: P
authors.lastname: Kumar
authors.forename: Poul
authors.initials: P
authors.lastname: Nielsen
authors.forename: Pawan K
authors.initials: PK
authors.lastname: Sharma
mesh_terms: D000114:Acetylene / Q000031:analogs & derivatives; D001483:Base Sequence; D003857:Deoxyuridine / Q000138:chemical synthesis / Q000737:chemistry*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009696:Nucleic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D009711:Nucleotides / Q000138:chemical synthesis / Q000737:chemistry*; D013941:Thymine / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D009696:Nucleic Acids; D009711:Nucleotides; D000114:Acetylene; D013941:Thymine; D003857:Deoxyuridine