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-(3,4-dihydroxyphenyl)-N-(4,5-dimethylpyrimidin-2-yl)-N-(4-sulfamoylphenyl)prop-2-enamide into molecular formula.
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C21H20N4O5S
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