You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(6-chloro-1,3-benzothiazol-2-yl)-2-[(5S,6R)-6-methoxy-1-oxa-9-azaspiro[4.5]decan-9-yl]acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H22ClN3O3S
assistant