You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3aR,6aS)-1-(2,3-dimethylphenyl)-5,5-dioxo-3a,4,6,6a-tetrahydro-3H-thieno[3,4-b]pyrrol-2-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C14H17NO3S
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