[Methoxymethyl and (p-nitrobenzyloxy)methyl groups in the synthesis of oligoribonucleotides by the phosphotriester method].

An efficient synthetic method for monomer ribonucleotide synthons containing 2'-O-methoxymethyl and 2'O-(p-nitrobenzyloxy)methyl groups used for oligonucleotide phosphotriester method with O-nucleophilic intramolecular catalysis at the stage of formation of internucleotide bond is developed. It is shown that synthons containing protecting 2'-O-(p-nitrobenzyloxy)methyl group may be used for automatic synthesis of phosphotriester oligoribonucleotides with high yields and synthons containing methoxymethyl group--to get 2'-O-modified oligonucleotides.