N-Methylpiperazinocarbonyl-2,3-BcNA and 4-C-(N-methylpiperazino)methyl-DNA: introduction of basic functionalities facing the major groove and the minor groove of a DNA:DNA duplex

Piperazino-functionalized 2ʹ,3ʹ-BcNA and 4ʹ-C-hydroxymethyl-DNA are appropriate molecular architectures for the introduction of basic functionalities facing the major groove and the minor groove of nucleic acid duplexes, respectively. 4ʹ-C-(N-Methylpiperazino)methyl-DNA monomers induce significantly increased thermal stability of a DNA:DNA duplex.