You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[2-[(2-butoxy-5-chlorophenyl)methylidene]hydrazinyl]-6-oxo-4-phenyl-1H-pyrimidine-5-carbonitrile is the IUPAC name of a molecule. Please give its molecular formula.
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C22H20ClN5O2
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