You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3-(4-methylpyrazol-1-yl)-1-[4-(6-methylthieno[2,3-d]pyrimidin-4-yl)piperazin-1-yl]propan-1-one into its molecular formula.
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C18H22N6OS
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