Oligonucleotides containing 4'-C-aminomethyl-2'-modified thymidines show increased binding affinity towards DNA and RNA.

Oligonucleotides containing 4'-C-aminomethyl-2'-O-methyl or 4'-C-aminomethyl-2'-deoxy-2'-fluoro modified thymidines have been synthesized. Compared with the corresponding oligodeoxynucleotide reference these novel oligonucleotide analogues display increased binding affinity towards complementary single stranded DNA as well as RNA. The possible effect of the positively charged 4'-C-aminomethyl group has been investigated.