You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named [(1S)-2-(3,5-dichloropyridin-1-ium-4-yl)-1-(3,4-dimethoxyphenyl)ethyl] 5-formylthiophene-3-carboxylate;hydroxide is given. What is its corresponding molecular formula?
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C21H19Cl2NO6S
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