methyl 4,7,8,9-tetra-O-acetyl-2,6-anhydro-5-(benzyloxyacetamido)-3,5-dideoxy-D-glycero-D-galactonon-2-enonate 、
乙腈 在
硫酸 作用下,
反应 0.5h,
以76%的产率得到methyl 4-acetamido-7,8,9-tri-O-acetyl-2,6-anhydro-5-(benzyloxyacetamido)-4,3,5-trideoxy-D-glycero-D-talonon-2-enonate