You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name tert-butyl 2-[4-[(2,4-dichlorophenyl)-hydroxymethyl]phenyl]-4,5-dihydroimidazole-1-carboxylate into its molecular formula.
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C21H22Cl2N2O3
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