You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(Z)-[[3-(2-chlorophenyl)-1,2,4-oxadiazol-5-yl]-nitromethylidene]amino]-N-phenylaniline The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H14ClN5O3
assistant