[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is an alpha-D-GalpNAc-(1->3)-D-GalpNAc having beta-configuration at the reducing end anomeric centre. It has a role as an antigen and an epitope."}, {"from": "gpt", "value": "[C][C][=Branch1][C][=O][N][C@@H1][C@H1][Branch2][Ring2][=Branch2][C@H1][Branch2][Ring2][Ring2][C@H1][Branch2][Ring1][=C][O][C@@H1][Ring1][=Branch1][O][C@@H1][C@H1][Branch1][#C][C@@H1][Branch1][O][O][C@@H1][Branch1][Branch1][C@@H1][Ring1][=Branch1][O][C][O][O][N][C][=Branch1][C][=O][C][C][O][O][O]"}]