[{"from": "human", "value": "Synthesize a molecule that matches the given characteristics. The molecule is a (3R,4R)-3-acyl-4-(hydroxymethyl)oxolan-2-one."}, {"from": "gpt", "value": "[C][C][C][Branch1][C][C][C][C][C][C][C][=Branch1][C][=O][C@H1][C@@H1][Branch1][#Branch1][C][O][C][Ring1][Branch1][=O][C][O]"}]