You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 6-(chloromethyl)-4-(4-ethylphenyl)-2-oxo-3,4-dihydro-1H-pyrimidine-5-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C16H19ClN2O3
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