You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(diethylamino)ethyl 2-[3-methyl-5-[5-(3-methylsulfonylphenyl)-1,3,4-thiadiazol-2-yl]pyrazol-1-yl]acetate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H27N5O4S2
assistant