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 N-[2-[2-[4-amino-2-(2-methoxyethyl)imidazo[4,5-c]quinolin-1-yl]ethoxy]ethyl]butane-2-sulfonamide into molecular formula.
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C21H31N5O4S
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