You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
7,7-dimethyl-4-(4-methylsulfanylphenyl)-3,4-dihydro-1H-furo[3,4-b]pyridine-2,5-dione The above is the IUPAC name of a molecule. Write its molecular formula.
user
C16H17NO3S
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