You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[2-[1-[2-[bis(2-methylpropyl)amino]-2-oxoethyl]benzimidazol-2-yl]ethyl]-2-methylbenzamide into molecular formula.
user
C27H36N4O2
assistant