You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 2-(5-morpholin-4-ylsulfonylthiophen-2-yl)-1-[4-[3-(trifluoromethyl)phenyl]piperazin-1-yl]ethanone .
user
C21H24F3N3O4S2
assistant