You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[1-(7-chloro-3-methyl-4-oxoquinazolin-2-yl)ethyl]-1-ethyl-3-(4-ethylphenyl)urea by IUPAC nomenclature, provide its molecular formula.
user
C22H25ClN4O2
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