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 ethyl (4S)-1-acetyl-6-methyl-4-(3-methylphenyl)-2-(2-methyl-1,3-thiazol-4-yl)-4H-pyrimidine-5-carboxylate into molecular formula.
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C21H23N3O3S
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