Solid phase synthesis of oligoribonucleotides using o-nitrobenzyl protection of 2′-hydroxyl via a phosphite triester approach

Abstract
The hepta and undecaribonucleotide were synthesized on a controlled pore glass beads using o-nitrobenzyl protection of 2′-hydroxyls via a phosphite approach. By using 5-p-nitrophenyltetrazole for the activation of nucleoside-phosphoramidite, the condensation reaction was carried out very rapidly (2.5min). The time required for one cycle was only 16min. The hepta-(UACUAAC) and undecaribonucleotides(GUAUGUUAAUA) were obtained in yields of 28 and 17% respectively from the original resin.