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 1-[6-[2-(3-fluoroanilino)-2-oxoethyl]-7-oxo-[1,3]thiazolo[4,5-d]pyrimidin-2-yl]-N-methylpiperidine-4-carboxamide .
user
C20H21FN6O3S
assistant