You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named ethyl (4S)-4-[[6-[2-(methoxymethyl)phenyl]-[1,2,4]triazolo[1,5-a]pyridin-2-yl]carbamoyl]-1,3-thiazolidine-3-carboxylate by IUPAC nomenclature, provide its molecular formula.
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C21H23N5O4S
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