Practical synthesis of [1-13C]- and [6-13C]-d-galactose

The chemical synthesis of 13C-labeled d-galactose as useful molecular probes for studying the conformation of oligosaccharides attached to proteins was performed. The method for synthesizing the title labeled compounds was newly developed via the corresponding 1-ene and 5-ene compounds derived from 1,2:5,6-di-O-isoproppylidene-α-d-galactofuranose by considering the efficient introduction of the atom. All protons of galactose from H-1 to H-6 were observed by the HMQC–HOHAHA technique using 1:1 mixtures of methyl [1-13C]- and [6-13C]-β-d-galactopyranoside, which were prepared from the title compounds.