[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is a trisaccharide derivative consisting of three 3-deoxy-alpha-D-manno-oct-2-ulopyranonosyl units in a linear sequence with an O-allyl group at the anomeric centre. It has a role as an antigen."}, {"from": "gpt", "value": "[C][=C][C][O][C@@][Branch2][#Branch1][Branch1][C][C@H1][Branch1][P][C@H1][Branch1][=N][C@H1][Branch1][Ring2][O][Ring1][=Branch1][C@@H1][Branch1][Ring1][C][O][O][O][O][C@@][Branch2][Branch1][#Branch1][C][C@H1][Branch2][Ring2][P][C@H1][Branch2][Ring2][N][C@H1][Branch1][Ring2][O][Ring1][=Branch1][C@@H1][Branch2][Ring1][P][C][O][C@@][Branch2][Ring1][=Branch1][C][C@H1][Branch1][P][C@H1][Branch1][=N][C@H1][Branch1][Ring2][O][Ring1][=Branch1][C@@H1][Branch1][Ring1][C][O][O][O][O][C][=Branch1][C][=O][O][O][O][O][C][=Branch1][C][=O][O][C][=Branch1][C][=O][O]"}]