You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name N-[(5-bromothiophen-2-yl)methyl]-N-ethyl-2-(4-oxo-1-phenylpyrazolo[3,4-d]pyrimidin-5-yl)acetamide into its molecular formula.
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C20H18BrN5O2S
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