You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[3-(4-fluorophenyl)imidazol-4-yl]-[4-[(E)-2-phenylethenyl]sulfonylpiperazin-1-yl]methanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H21FN4O3S
assistant