You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the compound with this IUPAC name (2Z)-3-ethyl-2-[(1-methylquinolin-1-ium-4-yl)methylidene]-6,7-dihydro-[1,4]dioxino[2,3-f][1,3]benzothiazole ?
user
C22H21N2O2S+
assistant