Atomic structure
There is only one chemically distinct structure:
[1*]O[C@@H]1[C@H](O[C@]2(C(=O)O)C[C@@H](O)[C@@H](O)[C@@H]([C@H](O)CO)O2)C[C@](O)(C(=O)O)O[C@@H]1[C@H](O)COR1 = core oligosaccharide