You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [(2R,3S)-3-amino-4-(3,5-difluorophenyl)-1-[(3-ethylphenyl)methylamino]butan-2-yl] 2-hydroxy-4-oxo-4-thiophen-3-ylbutanoate by IUPAC nomenclature, provide its molecular formula.
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C27H30F2N2O4S
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