Synthesis and Base Pairing Properties of 1′,5′-Anhydro-L-Hexitol Nucleic Acids (L-HNA)

Oligonucleotides composed of 1'-5'-anhydor-arabino-hexitol nucleosides belonging to the L series (L-HNA) were prepared and preliminary studied as a novel potential base-pairing,, system. Synthesis of enantiopureL-hexitol hexitol nucleotide monomers equipped with a 2'-(N-6-benzoyladenin-9-yl) or a 2'-(thymin-1-yl) moiety was carried out by a de novo approach based on a domino reaction as key step. The L oligonucelotide analogues lucre evaluated in duplex formation with natureal complements as well as with unnatural sugar-modified oligonucelotide. In many cases stable homo- mid hetero-chiral assciations lucre found Besides Tm measurements, detection of heterochiral complexes was unambiguously confirmed by LC-MS studies Interestingly, circular dichroism measurements of the most stable duplexes suggested that L-HNA form left-handed helices with both D and L oligonucelotides.