You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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4-[(2S,3S)-2-amino-3-methylpentoxy]-5-[(3,4-difluorophenyl)carbamoyl]-1-methylpyrrole-3-sulfinic acid is the IUPAC name of a molecule. Please give its molecular formula.
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C18H23F2N3O4S
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