You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[4-[4-(azepan-1-ylsulfonyl)-2-nitrophenyl]piperazin-1-yl]-1-morpholin-4-ylethanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H33N5O6S
assistant