You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[5-[1-(2,5-dimethoxyphenyl)ethylsulfamoyl]-1,3,4-thiadiazol-2-yl]benzamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H20N4O5S2
assistant