of the synthesis, the bromine was removed together with a benzyl protecting group by catalytic reduction with ammonium formate to give the required LNA monomers. An allopurinol lockednucleicacid (LNA) monomer was prepared by a novel strategy through C6 deamination of the corresponding 8-aza-7-bromo-7-deazaadenine LNA monomer with aqueous sodium hydroxide. An 8-aza-7-deazaadenine LNA monomer was also