You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[[(5S)-3-(3-chlorophenyl)-2-oxo-1,3-oxazolidin-5-yl]methyl]-3-(3-methylphenyl)urea into its molecular formula.
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C18H18ClN3O3
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