title: The influence of modified purine bases on the stability of parallel DNA.
abstract: The stability of the parallel-stranded (ps) DNA duplexes is increased when the dA-residues are replaced by the 7-substituted 7-deaza-2'-deoxyadenosine derivatives 3a,b or the dG-residues by the 8-aza-7-deazapurine 2'-deoxynucleosides 6 and 7a,b. Also the N-7-glycosylated adenine 5 forms stable base pairs in ps-DNA while it destabilizes oligonucleotide duplexes with antiparallel chain orientation. The presence of a 2-amino group as in compound 4b is critical for the DNA-structure, leading to a much greater destabilization of the ps-hybrids than of aps-DNA.
authors.affiliation: Laboratorium für Organische und Bioorganische Chemie, Institut für Chemie, Universität Osnabrück, Germany. fraseela@rz.uni-osnabrueck.de
authors.forename: F
authors.initials: F
authors.lastname: Seela
authors.forename: C
authors.initials: C
authors.lastname: Wei
authors.forename: G
authors.initials: G
authors.lastname: Becher
authors.forename: M
authors.initials: M
authors.lastname: Zulauf
authors.forename: P
authors.initials: P
authors.lastname: Leonard
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D011687:Purines / Q000737:chemistry*
chemical_list: D011687:Purines; D004247:DNA