You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[4-[[2-[[3-(1,3-benzothiazol-7-yloxy)-2-hydroxypropyl]-methylamino]-2-iodopropyl]amino]-4-oxobutyl] nitrate is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H25IN4O6S
assistant