You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [(2S)-1-[4-[(2S)-butan-2-yl]anilino]-1-oxopropan-2-yl] 2-chloro-5-methylsulfonylbenzoate into its molecular formula.
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C21H24ClNO5S
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