Synthesis and structural study of ribo-dioxaphosphorinane-constrained nucleic acid dinucleotides (ribo-α,β-D-CNA)

Article abstract of DOI:10.1002/ejoc.201101353

With increasing interest in the control of the conformations of nucleic acids to define active riboswitch or siRNA, we present herein our efforts towards the stereocontrolled synthesis and conformational analysis of ribodinucleotides in which α and β torsional angles are constrained within a dioxaphosphorinane structure (ribo-α,β-D-CNA). The crystal structure analysis of one α,β-D-CNA TU dimer demonstrates the absolute stereochemistry of the newly created asymmetric centres. NMR and CD analyses allowed complete assignment and the determination of the torsional angles in the α,β-D-CNA UU diastereoisomers. Diastereoisomers of α,β-D-CNA ribodinucleotide building blocks of nucleicacids in which the α and β torsional angles are stereocontrolled by a dioxaphosphorinane ring structure (D-CNA family) have been synthesised. The structural analyses showed that these dinucleotides exhibit a South/North junction associated with either canonical or non-canonical states of the sugar phosphate backbone. Copyright