You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-O-ethyl 2-O-(2-methoxyethyl) 5-[[1-(2-cyanoethyl)piperidine-3-carbonyl]amino]-3-methylthiophene-2,4-dicarboxylate into its molecular formula.
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C21H29N3O6S
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