You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-hydroxy-6-oxo-7H-thieno[2,3-b]pyridine-5-carboxylic acid The above is the IUPAC name of a molecule. Write its SMILES notation.
user
O=C(O)C1=C(O)C2=C(NC1=O)SC=C2
assistant