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 [4-[2-nitro-4-(trifluoromethyl)phenyl]piperazin-1-yl]-(1,3,6-trimethylpyrazolo[3,4-b]pyridin-4-yl)methanone .
user
C21H21F3N6O3
assistant