You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(E)-1-phenyl-3-(4-pyrrolidin-1-ylpyridin-1-ium-1-yl)prop-2-en-1-one;chloride The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H19ClN2O
assistant