You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[4-(4,4-dimethylpiperidin-1-yl)-5-(4-methoxyphenyl)-2-methylpyridin-3-yl]acetic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H28N2O3
assistant