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 N-[(3aS,4R,6aR)-2,2-dimethyl-6-[(E)-2-methylsulfonylethenyl]-4,5,6,6a-tetrahydro-3aH-cyclopenta[d][1,3]dioxol-4-yl]-2,5,6-trimethylpyrimidin-4-amine into molecular formula.
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C18H27N3O4S
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