You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
7-(3-methoxyphenyl)-3-(4-methylphenyl)-5-oxo-6,7-dihydro-4H-thieno[3,2-b]pyridine-2-carboxylic acid The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H19NO4S
assistant