You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule methyl 6-acetyl-2-[(2-chlorobenzoyl)amino]-5,7-dihydro-4H-thieno[2,3-c]pyridine-3-carboxylate into molecular formula.
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C18H17ClN2O4S
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