Nucleosides and oligonucleotides having 2'-ether groups

Abstract

Compounds of the formula ##STR1## are described wherein R.sub.1 and R.sub.2 are each independently of the other hydrogen or a protecting group, or R.sub.1 has those definitions and R.sub.2 is a radical forming a phosphorus-containing nucleotide bridge group; B is a purine or pyrimidine radical or an analogue thereof; and R.sub.3 is a radical of formula Ia, Ib or Ic ##STR2## wherein R.sub.4 is hydrogen, C.sub.1 -C.sub.21 alkyl, C.sub.2 -C.sub.21 alkenyl, C.sub.2 -C.sub.21 alkynyl or --C(.dbd.O)-alkyl; R.sub.5 is hydrogen, C.sub.1 -C.sub.10 alkyl, --CH.sub.2 --O--R.sub.6 or a radical of formula Ib; R.sub.6 is hydrogen, C.sub.1 -C.sub.22 alkyl, C.sub.3 -C.sub.21 alkenyl, or partially or completely fluorine-substituted C.sub.1 -C.sub.10 alkyl or --[(CH.sub.2).sub.2 --O].sub.m --R.sub.7 ; R.sub.7 is hydrogen or C.sub.1 -C.sub.21 alkyl; Z is --(CH.sub.2).sub.p -- or --(CH.sub.2 --CH.sub.2 --O).sub.q --CH.sub.2 CH.sub.2 --, it being possible for Z in the case of --CH.sub.2 -- to be unsubstituted or substituted by one or more identical or different substituents selected from C.sub.1 -C.sub.10 alkyl, C.sub.5 -C.sub.6 cycloalkyl and unsubstituted or C.sub.1 -C.sub.4 alkyl-substituted phenyl; n is a number from 1 to 12; m is a number from 1 to 4; p is a number from 1 to 10; and q is a number from 1 to 4.

Dependencies are inferred from the claim text.