You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2Z)-2-(1-chloroethenyl)-N-[4-(5-chloro-2-methyl-1,3-benzoxazol-6-yl)phenyl]penta-2,4-dienamide into its molecular formula.
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C21H16Cl2N2O2
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