Convenient chemoenzymatic synthesis of β-purine-diphosphate sugars (GDP-fucose-analogues)

A series of peracetylated β-sugar-1-phosphates with l-fuco configuration are efficiently prepared chemically and coupled in high yield to purine monophosphate bases via imidazolide activation. The resulting purine diphosphate sugars are deacetylated completely by a mild treatment with commercial acetylesterase (EC 3.1.1.6) to give donor-substrates for fucosyltransferases. A versatile high-yielding synthesis of nucleotide-diphosphate sugars is presented. Chemically synthesized peracetylated β-fucose-1-phosphate derivatives were coupled to purine monophosphates via imidazolide activation. Complete deacetylations of the resulting purine-diphosphate sugars were achieved by treatment with commercial acetylesterase.