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-[4-[[5-(furan-2-yl)-1,2-oxazol-3-yl]methyl]piperazin-1-yl]sulfonylbenzonitrile by IUPAC nomenclature, provide its molecular formula.
user
C19H18N4O4S
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