You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[3-(3-chlorophenyl)-7-[2-(1-methylpiperidin-4-yl)ethoxy]-1-oxopyrrolo[1,2-a]pyrazin-2-yl]-N-propan-2-ylacetamide by IUPAC nomenclature, provide its molecular formula.
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C26H33ClN4O3
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