[{"from": "human", "value": "Describe this molecule. [C][C@H1][Branch2][Ring1][Ring2][C][=C][Branch1][O][O][C@@H1][Ring1][=Branch1][C@@H1][Branch1][Ring1][C][O][O][C][=Branch1][C][=O][O][O][C][C@H1][Branch2][Ring1][#Branch2][C@@H1][C@@H1][Branch2][Ring1][Ring2][C@@H1][Branch1][S][C][C@@][Branch1][Ring2][O][Ring1][=Branch1][Branch1][=Branch1][C][=Branch1][C][=O][O][O][O][O][O]"}, {"from": "gpt", "value": "The molecule is a carbohydrate acid comprising 3-deoxy-alpha-D-manno-oct-2-ulopyranosonic acid (Kdo) having a 5-deoxy-4-epi-2,3-dehydro-Kdo moiety attached via an unusual (4->8) non-glycosidic linkage. It is functionally related to a 3-deoxy-alpha-D-manno-oct-2-ulopyranosonic acid."}]