ethyl 3,4-O-isopropylidene-6-O-tert-butyldimethylsilyl-2-O-methanesulfonyloxyethyl-1-thio-β-D-galactopyranoside

ethyl 2-O-(3,3-di-tert-butyloxycarbonylpropyl)-4,6-O-benzylidene-1-thio-β-D-galactopyranoside

ethyl 3,4-O-isopropylidene-6-O-tert-butyldimethylsilyl-2-O-(3,3-di-tert-butyloxycarbonylpropyl)-1-thio-β-D-galactopyranoside