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 7-ethyl-2-[(1-methylsulfanylcyclopropyl)methylamino]-[1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one into molecular formula.
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C12H16N4OS2
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