You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(3-chlorophenyl)-3-[[5-[(2-fluorophenoxy)methyl]-4-prop-2-enyl-1,2,4-triazol-3-yl]sulfanyl]propanamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H20ClFN4O2S
assistant