Base-modified oligodeoxynucleotides. I. effect of 5-alkyl, 5-(1-alkenyl) and 5-(1-alkynyl) substitution of the pyrimidines on duplex stability and hydrophobicity

Abstract Properties of oligodeoxynucleotides essential for the antisense effect can be favourably modified by substitution of the heterocyclic base moiety. This is shown here for duplex stability by 5 alkyl, 5-(1-alkenyl) and 5-(1-alkynyl) substitution of the pyrimidines in the self-complementary (dT-dA) 10 and (dC-dG) 6 oligomers as well as for the hydrophobic character of the (dT-dA) 10 series.