Synthesis of 1-(5-amino-3,5-dideoxy-3-methoxycarbonylmethyl-β-d-ribofuranosyl)thymine

In order to synthesize amide-linked antisense oligonucleotides, a general chemical approach was developed for the synthesis of building blocks in which an amino group and a carboxylic group are contained at the 5′ and 3′ positions of a nucleoside.