You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(1,3-benzodioxol-5-ylmethyl)-3-[2-(2-methoxyphenyl)-1,3-thiazol-4-yl]propanamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H20N2O4S
assistant