You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 6-(4-methylsulfinyl-1,3-benzoxazol-2-yl)-3-phenyl-2-(trifluoromethyl)-2,3,3a,4-tetrahydro-1H-pyrazolo[1,5-a]pyrimidin-7-one by IUPAC nomenclature, provide its molecular formula.
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C21H17F3N4O3S
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