Nucleosides and nucleotides. 170. Synthesis and properties of oligodeoxynucleotides containing 5-[N-[2-[N,N-bis(2-aminoethyl)- amino]ethyl]carbamoyl]-2'-deoxyuridine and 5-[N-[3-[N,N-bis(3-aminopropyl) amino]propyl]carbamoyl]-2'-deoxyuridine.

The synthesis of oligodeoxynucleotides (ODNs) containing 5-[N-[2-[N,N-bis(2-aminoethyl)amino]ethyl]-carbamoyl]-2'-deoxyuridine (BAE) and 5-[N-[3-[N,N-bis(3-aminopropyl)amino]propyl]carbamoyl]-2'- deoxyuridine (BAP) is described. The thermal stabilities of duplexes containing these ODNs and either the complementary DNA or RNA strand and of triplexes consisting of these ODNs and the target duplex were studied by thermal denaturation. ODNs containing BAE or BAP stabilize duplex formation with either the complementary DNA or RNA strands but destabilize triplex formation with the target duplex. Furthermore, the resistance of these ODNs to nuclease hydrolysis was studied by using snake venom phosphodiesterase (a 3'-exonuclease) and nuclease S1 (an endonuclease). It was found that ODNs containing either BAE or BAP were more resistant to nucleolytic hydrolysis by either of the nucleases than the unmodified ODN.