You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-(3,4,6,7,8,8a-hexahydro-1H-pyrrolo[1,2-a]pyrazin-2-yl)-N-methylthieno[2,3-d]pyrimidin-2-amine into its molecular formula.
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C14H19N5S
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