You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-(3,4-dichlorophenyl)-2-[6-(3-isocyanophenyl)-1'-propan-2-ylspiro[3,4-dihydroisoquinoline-1,4'-piperidine]-2-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
user
C31H32Cl2N4O
assistant