You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[1-[4-[5,7-dimethyl-2-(2-methylpropyl)imidazo[4,5-b]pyridin-3-yl]phenyl]ethyl]-3-methylbutanoic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C25H33N3O2
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