You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[2-(2-ethyl-1,3-thiazol-4-yl)ethyl]-3-[(1R,2S)-2-(4-methoxyphenyl)cyclopropyl]urea The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H23N3O2S
assistant