Novel anthraquinone conjugate of 2,2-bis(hydroxymethyl)propionic acid incorporated to a TFO with phosphodiester linkage facilitates triplex formation with dsDNA bearing a pyrimidine-gapped polypurine sequence.

An anthraquinone derivative conjugated with 2,2-bis(hydroxymethyl)propionic acid as a novel non-nucleosidic component was synthesized and successfully incorporated into an internal region of 14-mer triplex-forming oligonucleotide (TFO) via the phosphoramidite method. The resulted novel TFO exhibits remarkable enhancement effect on the thermal stability of a DNA triplex upon binding to a pyrimidine-gap containing polyprurine sequence.