D-Altritol Nucleic Acids (ANA): Hybridisation Properties, Stability, and Initial Structural Analysis

Abstract

Oligonucleotides composed of a phosphorylated D-altritol backbone (see diagram) with nucleobases in the 2′-position, hybridise strongly and sequence selectively with RNA in an antiparallel way (dsANA>ANA:RNA>ANA:DNA). Complexes between ANA and RNA or DNA are more stable than between HNA and natural oligonucleotides. A hexamer dsANA hybrid gives a ΔTm per modification of +10.2 °C relative to an identical dsDNA sequence. CD spectral analysis indicates that ANA complexes are very similar to the A-form dsRNA duplex.