Mesylate (II), prepared from the (hydroxymethyl)phosphinic acid derivative (I), was condensed with the protected glucosamine (III) in the presence of NaH to produce the phosphinate adduct (IV) as a diastereomeric mixture. Selective removal of the P-acetyl ketal group of (IV) with chlorotrimethylsilane and a trace of water gave rise to the deprotected phosphinate (V). This was subjected to Arbuzov reaction with methyl (bromomethyl)acrylate (VI) under silylating conditions to afford the substituted phosphinate (VII). Concomitant double-bond hydrogenation and hydrogenolysis of the benzyl and benzylidene groups of (VII) was effected by hydrogenation over Pd/C. The resulting product (VIII) was then peracetylated with acetic anhydride/pyridine to give the triacetate (IX). Treatment of (IX) with aminoethanol in THF selectively removed the anomeric acetate to produce (X) as a complex diastereomeric mixture.

Treatment of (X) with BuLi and diphenyl chlorophosphate led to stereoselective formation of the alpha phosphate ester (XI). The phenyl phosphate ester groups of (XI) were then deprotected by catalytic hydrogenation over PtO2 to afford (XII), isolated as a mixture of two major diastereomers. Coupling of (XII) with uridine monophosphate morpholidate (XIII) led to the uridine diphosphate-containing derivative (XIV). Finally, saponification of the ester groups of (XIV) with aqueous NaOH furnished the title compound.