Synthesis and Structure of Dinucleotides Featuring Canonical and Non‐canonical A‐Type Duplex α, β and δ Torsion Angle Combinations (LNA/α,β‐D‐CNA)
The synthesis of diastereoisomers of LNA/α,β-D-CNA dinucleotide building units of nucleic acids in which one δ torsional angle is constrained by an LNA structure and the α and β torsional angles are stereocontrolled by a dioxaphosphorinane ring structure (D-CNA family) is described. NMR structural analysis showed that the δa, αb and βb torsional angles of the (RC5′,RP)-configured LNA/α,β-D-CNA TT dimer are restricted to the canonical {δa,αb,βb} = {gauche(+)/anticlinal(+), gauche(–), trans} conformation typically observed in A-type duplexes. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)