You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by N-[2-[4-(5-chloro-4-methyl-1,3-benzothiazol-2-yl)piperazin-1-ium-1-yl]ethyl]-2-methylpropanamide ?
user
C18H26ClN4OS+
assistant