You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (E)-N-[4-(4-chlorophenyl)-1,3-thiazol-2-yl]-3-(2,3-dimethoxyphenyl)prop-2-enamide by IUPAC nomenclature, provide its molecular formula.
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C20H17ClN2O3S
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