You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule 2-[2-(4-ethylanilino)-2-oxoethyl]sulfonyl-N-(5-ethyl-1,3,4-thiadiazol-2-yl)butanamide ?
user
C18H24N4O4S2
assistant