NUCLEOSIDES AND NUCLEOTIDES .121. SYNTHESIS OF OLIGONUCLEOTIDES CARRYING LINKER GROUPS AT THE 1'-POSITION OF SUGAR RESIDUES

Novel 2'-deoxyuridine analogues carrying aminoalkyl linkers at the 1'- position of the sugar residues were synthesized and incorporated into oligonucleotides, then intercalating groups such as an anthraquinone d erivative and a pyrene derivative were attached to the amino groups. D uplexes consisting of the oligonucleotides carrying the linker groups and a complementary ribonucleotide were more stable than an unmodified parent duplex, but the duplexes consisting of the oligonucleotides an d a complementary deoxyribonucleotide were less stable. The oligonucle otides carrying the linker groups were more resistant to nuclease P1 a nd venom phosphodiesterase than an unmodified oligonucleotide. Further more, a duplex formed by the oligonucleotide analogue and the compleme ntary ribonucleotide was a substrate for ribonuclease H.