You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-amino-4-(4-chlorophenyl)-7-methyl-6-[(4-methylphenyl)methyl]-5-oxo-4H-pyrano[3,2-c]pyridine-3-carbonitrile is the IUPAC name of a molecule. Please give its molecular formula.
user
C24H20ClN3O2
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