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 (E)-3-(3-chloro-4,5-dimethoxyphenyl)-N-[2-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)ethyl]prop-2-enamide into molecular formula.
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C20H23ClN2O3S
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