You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule 2-[4-(4-bromophenyl)sulfonylpiperazin-1-yl]-N-[(E)-[(Z)-3-(2-nitrophenyl)prop-2-enylidene]amino]acetamide ?
user
C21H22BrN5O5S
assistant