PROCESS FOR PREPARING ZANAMIVIR AND INTERMEDIATES FOR USE IN THE PROCESS

摘要

The present invention provides a process for preparing methyl 5-acetamido-4-amino-6- (1,2,3-triacetoxypropyl)-5,6-dihydro-4H-pyran-2-carboxylate (V), which process comprises reducing methyl 5-acetamido-4-azido-6-(1,2,3-triacetoxypropyl)-5,6-dihydro-4H-pyran-2- carboxylate (IV) in the presence of a reducing agent selected from the group consisting of lithium aluminium hydride, sodium borohydride, zinc/ammonium chloride, zinc-ferric chloride and ferric chloride/sodium iodide. The present invention also provides compounds of formula (VIII) and (IX) which may be used in the synthesis of zanamivir. The present invention also provides processes for preparing compounds (VIII) and (IX) and processes involving their use, including in the synthesis of zanamivir.