Abstract
Selective protection of the C-4, C-8, and C-9 hydroxy groups of methyl (methyl 5-acetamido-3, 5-dideoxy-D-glycero-α-D-galacto-nonulopyranosid) onate followed by acetylation of the C-7 hy-droxy group gave a 7-O-acetyl-N-acetylneuraminic acid derivative.