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 4-chloro-3-(2,3-dihydroindol-1-ylsulfonyl)-N-[5-(2-methylpropyl)-1,3,4-thiadiazol-2-yl]benzamide into molecular formula.
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C21H21ClN4O3S2
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