The synthesis of N-acetyl-beta-L-fucosamine-1-phosphate and uridine 5 '-diphospho-N-acetyl-beta-L-fucosamine

Uridine 5'-(2-acetamido-2,6-dideoxy-beta -L-galactopyranosyl) diphosphate ( uridine 5'-diphospho-N-acetyl-beta -L-fucosamine) was synthesized. The key intermediate, 3,4-di-O-acetyl-2-azido-2,6-dideoxy-beta -L-galactopyranosyl dibenzyl phosphate. was prepared by a previously unknown reaction of cesium dibenzyl phosphate with the corresponding a-glycosyl nitrate and was then converted into the N-acetylated glycosyl phosphate and nucleoside diphospha te sugars via 3,4-di-O-acetyl-2-amino-2,6-dideoxy-beta -L-galactopyranosyl phosphate using mild N-acetylation and O-deacetylation as the last syntheti c steps.