You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule ethane;N-[[4-fluoro-2-(1,2,4-triazol-1-yl)phenyl]methyl]-3-hydroxy-9,9-dimethyl-4,8-dioxo-6,7-dihydropyrimido[2,1-c][1,4]thiazine-2-carboxamide into molecular formula.
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C21H25FN6O4S
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