Toward partial fucosyl transferase transition state analogues: methylene sulfono sulfonamide as surrogate of pyrophosphate

Partial fucosyl transferase transition state analogues having sulfonoacetamido- and methylene sulfono sulfonamide links as a non-charged surrogate of the pyrophosphate moiety have been prepared from fructose and guanosine. The use of a MOM group at N1 and a formamidine group at the primary amine function for the protection of the guanine residue proved troublesome.