You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 2-[4-[2-[[4-(2,5-difluorophenyl)-1,3-thiazol-2-yl]amino]-2-oxoethyl]piperazin-1-yl]-N-(2-methylpropyl)acetamide ?
user
C21H27F2N5O2S
assistant