You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-(4-chlorophenyl)-3-(3,5-dioxo-4-azatricyclo[5.2.1.02,6]dec-8-en-4-yl)-N-(5-ethyl-1,3,4-thiadiazol-2-yl)propanamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H21ClN4O3S
assistant