Large-scale synthesis of triple helix forming oligonucleotides using a controlled-pore glass support.

Triple helix forming oligonucleotides that involve purine:purine:pyrimidine interactions are purine-rich oligonucleotides containing 60%-90% G and are usually 25-40 bases long. Synthesis and purification of G-rich oligonucleotides of this length can be difficult even at small scales. Procedures to synthesize these compounds at 200 to 400 mumol scales with high coupling efficiency have been developed using a controlled-pore glass support.