2'-Aminoethoxy-2-amino-3-methylpyridine in Triplex-Forming Oligonucleotides: High Affinity, Selectivity and Resistance to Enzymatic Degradation

C. Lou, M. Shelbourne, K. R. Fox and T. Brown. Chem. Eur. J. 17 (52), 14851-14856, 2011.


The phosphoramidite monomer of the C-nucleoside 2'-aminoethoxy-2-amino-3-methylpyridine (AE-MAP) has been synthesized for the first time and incorporated into triplex-forming oligonucleotides (TFOs). Ultraviolet melting and DNase I footprinting studies show that AE-MAP is a potent triplex-stabilizing monomer that is selective for GC base pairs. TFOs containing AE-MAP bind with high affinity to duplexes but only weakly to single stranded DNA. In addition, AE-MAP confers high nuclease resistance on oligonucleotides. TFOs containing AE-MAP have potential for gene knock-out and gene expression studies.