You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Please write the molecular formula of the molecule ethyl 4-[3-[(3-chloro-1,2,4-thiadiazol-5-yl)amino]phenyl]-7-(propoxymethyl)pyrrolo[2,3-d]pyrimidine-5-carboxylate .
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C21H21ClN6O3S
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