Oligodeoxyribonucleotides containing 1,3-propanediol as nucleoside substitute

1,3-Propanediol was protected with one dimethoxytrityl residue and converted into the methoxy- and cyanoethoxyphosphoramidites 2a and 2b, respectively. Solid-phase oligonucleotide synthesis, employing the phosphoramidite 2a resulted in the dodecamers d(CGCGAATTCGCG) (6-9), in which dA or dT residues were replaced by 1,3-propanediol. These oligomers showed a high tendency to form hairpins. Their phosphodiester bonds between the 3'-position of a nucleoside and the propanediol moiety was not cleaved by snake venom phosphodiesterase.