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 (4aS,5R)-9-methoxy-N-(2-methylpropyl)-3-pyrazin-2-yl-1,2,4,4a,5,6-hexahydropyrazino[1,2-a]quinoline-5-carboxamide into molecular formula.
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C22H29N5O2
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