β-Stereoselective phosphorylations applied to the synthesis of ADP- and polyprenyl-β-mannopyranosides.

An efficient and convenient synthetic route to glycosyl 1-β-phosphates has been developed using diallyl chlorophosphate as a phosphorylating agent with 4-N,N-dimethylaminopyridine under mild conditions. Diallyl-glycosyl 1-β-phosphate triesters of D-manno, L-glycero-D-manno-hepto-, D-gluco-, D-galacto-, and L-fuco-pyranose as well as lactose have been obtained by this strategy in good yields and excellent β-selectivities. Furthermore, the diallyl 6-azido-mannosyl 1-β-phosphate 2 was deprotected under mild conditions and converted into potentially clickable analogues of β-mannosyl phosphoisoprenoids I and ADP-heptose II.