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 1-[4-(benzenesulfonyl)piperazin-1-yl]-2-[3,5-dimethyl-1-(2-methylpropyl)pyrazol-4-yl]ethanone into molecular formula.
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C21H30N4O3S
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