Synthesis of thioglycoside-based UDP-sugar analogues.

Arbuzov reaction of O-acetyl-protected glycosylthiomethyl chlorides with triethyl phosphite and then phosphonate ethyl ester cleavage with trimethylsilyl bromide afforded glycosylthiomethyl phosphonates 13, 18, 22, and 26. These intermediates could be readily transformed into the O-deprotected phosphonates 7-10 and into title compounds 1-4. Similarly, sulfonomethyl phosphonate moieties containing UDP-sugar analogues 5 and 6 were obtained.