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-chloro-N-[1-[[4-(4-methoxyphenyl)-5-methyl-1,3-thiazol-2-yl]amino]-1-oxopropan-2-yl]benzamide .
user
C21H20ClN3O3S
assistant