You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-(2-ethylpiperidin-1-yl)-3-(2-methyl-6-phenylimidazo[2,1-b][1,3,4]thiadiazol-5-yl)prop-2-en-1-one into its molecular formula.
user
C21H24N4OS
assistant