You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(2R)-1-(2-chloroanilino)-1-oxopropan-2-yl] 5-methyl-2-phenyl-1,3-oxazole-4-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H17ClN2O4
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