You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[1-[2-(dimethylamino)ethyl]indol-5-yl]-2-(2-oxopiperidin-1-yl)-2-phenylacetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C25H30N4O2
assistant