You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as 1-[(2-chloro-6-fluorophenyl)methyl]-N-(2-methoxy-5-nitrophenyl)piperidine-3-carboxamide using the IUPAC nomenclature.
user
C20H21ClFN3O4
assistant