You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the compound with this IUPAC name [5-chloro-1'-[(E)-3-(2-chloro-3,6-difluorophenyl)prop-2-enyl]spiro[2H-indole-3,4'-piperidine]-1-yl]-(2,6-dichloropyridin-4-yl)methanone ?
user
C27H21Cl4F2N3O
assistant