By condensation of pentafluorophenylsulfonyl chloride (I) with 3-fluoro-4-methoxyaniline (II) in pyridine.

The title sulfonamide was obtained by condensation of pentafluorophenyl sulfonyl chloride (I) with 3-hydroxy-4-methoxyaniline (II) in the presence of pyridine.

Condensation of pentafluorophenyl sulfonyl chloride (I) with 3-hydroxy-4-methoxyaniline (II) in the presence of pyridine afforded sulfonamide (III). Treatment of (III) with N,N-diisopropyl dibenzylphosphoramidite (A) and tetrazole gave phosphite ester (IV), which was subsequently oxidized to phosphate (V) by means of tert-butyl peroxide. Finally, hydrogenolysis of the benzyl phosphate ester groups of (V) in the presence of Pd/C and 1,4-cyclohexadiene furnished the title compound.