You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl 6-acetyl-2-[(1-thiophen-2-ylsulfonylpiperidine-2-carbonyl)amino]-5,7-dihydro-4H-thieno[2,3-c]pyridine-3-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H25N3O6S3
assistant