You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-(5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidin-2-yl)-N-[2-[4-(2-methyl-1,3-thiazol-4-yl)phenyl]ethyl]acetamide by IUPAC nomenclature, provide its molecular formula.
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C21H22N6OS
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