You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 3-(5-chloro-3-methyl-1,2-oxazol-4-yl)-N-[4-(4-methoxyphenyl)butan-2-yl]propanamide into molecular formula.
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C18H23ClN2O3
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