You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule N-[4-[4-[2-(diethylamino)-2-oxo-1-phenylethyl]piperidin-1-yl]-3-isocyanophenyl]-2-ethylbutanamide ?
user
C30H40N4O2
assistant