Syntheses of the 4-nitrophenyl glycosides of hyalobiuronic acid and chondrosine

4-Nitrophenyl [sodium β-d-glucopyranosyluronate]-(1→3)-2-acetamido-2-deoxy-β-d-glucopyranoside (1) and 4-nitrophenyl [sodium β-d-glucopyranosyluronate]-(1→3)-2-acetamido-2-deoxy-β-d-galactopyranoside (2) were prepared from the zwitterions hyalobiuronic acid [β-d-glucopyranuronic acid-(1→3)-2-amino-2-deoxy-d-glucopyranose] and chondrosine [β-d-glucopyranuronic acid-(1→3)-2-amino-2-deoxy-d-galactopyranose], respectively. Compounds 1 and 2 were not hydrolysed by bovine testicular hyaluronidase.