You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 2-imidazo[2,1-b][1,3]thiazol-6-yl-N-[3-methoxy-4-(2-oxopyrrolidin-1-yl)phenyl]acetamide into its molecular formula.
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C18H18N4O3S
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