You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-chloro-N-[(1R)-1-(3,4-difluorophenyl)ethyl]-4-methyl-5-nitrobenzenesulfonamide by IUPAC nomenclature, provide its molecular formula.
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C15H13ClF2N2O4S
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