Structure/affinity studies in the bicyclo-DNA series: Synthesis and properties of oligonucleotides containing bc(en)-T and iso-tricyclo-T nucleosides.

ABSTRACT: We present the synthesis of the two novel nucleosides iso-tc-T and bc(en)-T, belonging to the bicyclo-/tricyclo-DNA molecular platform. In both modifications the torsion around C6'-C7' within the carbocyclic ring is planarized by either the presence of a C6'-C7' double bond or a cyclopropane ring. Structural analysis of these two nucleosides by X-ray analysis reveals a clear preference of torsion angle γ for the gauche orientation with the furanose ring in a near perfect 2'-endo conformation. Both modifications were incorporated into oligodeoxynucleotides and their thermal melting behavior with DNA and RNA as complements was assessed. We found that the iso-tc-T modification was significantly more destabilizing in duplex formation compared to the bc(en)-T modification. In addition, duplexes

SUBMITTER: Dugovic B 

PROVIDER: S-EPMC4142851 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature