[{"from": "human", "value": "Provide a brief overview of this molecule. [C][C@@][Branch2][Ring1][#Branch1][O][C@H1][C@H1][Branch1][S][O][C@H1][Branch1][O][C@@H1][Branch1][#Branch1][C@H1][Ring1][=Branch1][O][Ring1][=Branch2][O][O][C][O][C][=Branch1][C][=O][O]"}, {"from": "gpt", "value": "The molecule is a carbohydrate derivative consisting of beta-D-galactose having a 1-carboxyethylidene group masking the 3-and 4-positions. It is a carbohydrate derivative and a cyclic ketal. It is functionally related to a D-galactopyranose."}]