UNG C1=C(O[C@@H]([C@@H]([C@H]1O)O)O[C@@H]2[C@@H]([C@H]([C@H](O[C@@H]2C(=O)O)O)O)O)C(=O)O 4-O-(4-DEOXY-BETA-L-THREO-HEX-4-ENOPYRANURONOSYL)-ALPHA-D-GALACTOPYRANURONIC ACID