You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (2R)-2-(3-chlorophenyl)-2-[2-[[2-(1,2-oxazol-3-yl)-1-benzofuran-5-yl]oxy]ethylamino]ethanol into molecular formula.
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C21H19ClN2O4
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