You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[5-(1,3-benzodioxol-5-yl)-1,3,4-thiadiazol-2-yl]-2-(2-chloropropanoylamino)-3-phenylpropanamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H19ClN4O4S
assistant