You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[[4-(5-chloro-2-methoxyphenyl)oxan-4-yl]methyl]-3-[(2,5-dimethylfuran-3-yl)methyl]urea The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H27ClN2O4
assistant