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Translate the chemical IUPAC name (8aS,9R)-6,6-dimethyl-9-(4-nitrophenyl)-2-(trifluoromethyl)-4,7,8a,9-tetrahydro-[1,2,4]triazolo[5,1-b]quinazolin-8-one into its molecular formula.
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C18H16F3N5O3
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