Sulfamide replacement of the phosphodiester linkage in dinucleotides: Synthesis and conformational analysis

Article abstract of DOI:10.1016/S0040-4020(97)10421-5

Dinucleotide analogues d(TnsnT) and d(TnsnA), in which the phosphodiester linkage of d(TpT) and d(TpA) is replaced by sulfamide [-NHSO₂NH-], have been synthesised. Conformational analysis using ³J vicinal coupling constants shows that this modification results in a shift from a predominantly southern (C2'-endo) to northern (C3'-endo) ribose ring conformation. The effect of temperature and concentration changes on ribose conformation, reveals that the modified dinucleosides have a greater propensity to base stack intramolecularly, and in the case d(TnsnA), self-associate.