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-[(2,3-dichlorophenyl)methyl]pyrazol-3-yl]-3-(5,6-dimethyl-4-oxothieno[2,3-d]pyrimidin-3-yl)propanamide into molecular formula.
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C21H19Cl2N5O2S
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