You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(5,6-dimethyl-1H-indol-2-yl)-3-(1,7-dimethyl-2-oxo-1,6-naphthyridin-3-yl)-4-methylbenzamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C28H26N4O2
assistant