Chemical synthesis and properties of an oligodeoxyribonucleotide containing a 2-deoxyribosylformamide residue

To elucidate the conformational properties of DNA with a 2-deoxyribosylformamide residue (dF), an oligodeoxyribonucleotide containing this abasic residue in a specific position of the nucleotide sequence was synthesized by the standard solid-phase phosphotriester method. Deprotection of the synthesized oligonucleotide was performed under routine alkaline and acidic conditions. The presence of a dF residue in the oligomer was confirmed by ion-spray mass spectrometry. A dF residue was found to affect considerably the stability of the DNA duplex, as determined from the melting behavior of the dF-containing duplex.