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,4R)-N-tert-butyl-3-(4-chlorobenzoyl)-2-(4-fluorophenyl)-1,3-thiazolidine-4-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C21H22ClFN2O2S
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