乙酸酐 、
methyl (benzyl 4-O-acetyl-5-azido-3,5-dideoxy-9-O-(4-methoxybenzyl)-D-glycero-α-D-galacto-non-2-ulopyranosid)onate 在
吡啶 作用下,
以91%的产率得到methyl (benzyl 4,7,8-tri-O-acetyl-5-azido-3,5-dideoxy-9-O-(4-methoxybenzyl)-D-glycero-α-D-galacto-non-2-ulopyranosid)onate