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-ethyl-2-[[(2S,4S)-2-methyl-1-prop-2-enoylpiperidin-4-yl]amino]-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide into molecular formula.
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C18H24N6O2
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