You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[4-[7-(4-ethoxyphenyl)-1H-imidazo[4,5-b]pyridin-2-yl]phenyl]-(4-methylpiperazin-1-yl)methanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C26H27N5O2
assistant