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 N-[[1-[6-[6-(difluoromethyl)imidazo[1,2-b]pyridazin-3-yl]pyrimidin-4-yl]-5-(3-fluoroazetidin-1-yl)piperidin-3-yl]methyl]methanesulfonamide .
user
C21H25F3N8O2S
assistant